The Political Economy and Metal Trade in Bronze Age Europe: Understanding Regional Variability in Terms of Comparative Advantages and Articulations

25 Pages·0.503 MB·English

by  Earle T. et al.

EuropeanJournalofArchaeology0(0)2015,1–25
The Political Economy and Metal Trade
in Bronze Age Europe: Understanding
Regional Variability in Terms of
Comparative Advantages and
Articulations
TIMOTHY EARLE1, JOHAN LING2, CLAES UHNÉR2, ZOFIA STOS-GALE2
AND LENE MELHEIM2
1Department of Anthropology, Northwestern University, USA
2Department of Historical Studies, University of Gothenburg, Sweden
In the second millennium cal BC, a new metal conquered Europe: the alloy of copper and tin that
improved the quality of tools and weapons. This development, we argue, initiated a framework for a
newpoliticaleconomy.WeexplorehowapoliticaleconomyapproachmayhelpunderstandtheEuropean
Bronze Age by focussing on regional comparative advantages in long-distance trade and resulting bot-
tlenecks in commodity flows. Links existed in commodity chains, where obligated labour and ownership
ofresourceshelpedmobilizesurpluses,thuscreatingpotentialforsocialsegmentstocontroltheproduction
and flows of critical goods. The political economy of Bronze Age Europe would thus represent a trans-
formationinhowwould-beleadersmobilized resourcestosupporttheirpoliticalends.Thelong-distance
trade in metals and other commodities created a shift from local group ownership towards increasingly
individual strategies to obtain wealth from macro-regional trade. We construct our argument to make
sense of available data, but recognize that our model’s primary purpose is to structure future research to
testthemodel.
Keywords: regional variability, metal trade, bottlenecks, social complexity, comparative advantage,
politicaleconomy
INTRODUCTION: THE POLITICAL to meet staple needs, social desires, and
ECONOMY OF BRONZE AGE EUROPE political strivings. A broadly integrated
regional and macro-regional economy, as
A political economy perspective on social seen during the Bronze Age (BA), can
stratification and centralized power looks emerge when comparative advantages exist
at the articulation between a society’s in resources and productive knowledge.
economy and institutional structure. Econ- Local populations typically have imperfect
omies are open systems that contain many access and knowledge of the many steps
commodity chains, encompassing steps in involved in commodity chains, and access
production, commodity flows, and con- and knowledge give advantages to certain
sumption. Local societies use economies localproducers, traders,warriors, travellers,
©EuropeanAssociationofArchaeologists2015 DOI10.1179/1461957115Y.0000000008
Manuscriptreceived15September2014,
accepted6March2015,revised30January2015
2 EuropeanJournalofArchaeology0(0)2015
and leaders. A potential can emerge to these were group-oriented chiefdoms, in
control material flows and so fuel inequal- which individuals were not particularly
ity and power relationships. distinguished, but the seeds of social
Based on a Marxist analysis generalized inequality were already planted.
to pre-modern economies, our approach to The shift from the Neolithic to the BA
prehistory investigates how economic was a profound structural transformation
power created a fluid socio-political based on a changing political economy
process (Earle, 1997; Rowlands & Ling, (Earle & Kristiansen, 2010). Large-scale
2013). How was BA society organized? trade in metals and other wealth across
Was it tribal, chiefdoms, or even states? Europe developed in the BA, because the
The answer is that it probably included new metal technology for tin-bronze
examples of many social formations based required copper and tin, two metals
on different local articulations with staple smelted from ores that typically derived
and wealth production and flows. Two from different regions, often quite distant
major paradigms are competing in BA from each other (Pare, 2000; O’Brien,
research: one that stresses elite-controlled 2014). Tin-bronze was used for weapons
long-distance trade networks (e.g. Kris- and tools and for prestige goods and jewel-
tiansen & Larsson, 2005; Kristiansen & lery, and their flows selectively transformed
Earle, 2014), another that stresses local local social institutions. In locations
processes and smaller-scale tribal or seg- removed from long-distance trade, group
mentary interaction (e.g. Harding, 2000, ownership of agro-pastoral resources would
2013; Kienlin, 2012, in press). Depending have continued largely unchanged from
on the European areas and archaeological Neolithic patterns. However, in areas
assemblages being considered, both argu- articulated with prestige goods flows, own-
ments may prove to be true, but to resolve ership of metal goods defined elite
these competing approaches requires sys- statuses, marked by displays seen in burials
tematic data collection. We focus on and hoards. In simple terms, the BA wit-
variability across Europe by outlining com- nessed an emergence of social stratification
modity chains for metal, and show how based on control over commodity flows.
different articulations may have created This new situation is what Renfrew (1984)
alternative means to establish exclusionary coined ‘individualizing chiefdoms’.
relationships in some areas, but not others. Fundamental to this transformation was
To understand the BA, we step back the nature of property relationships by
briefly to consider the Neolithic. Based on which local corporate ownership was indi-
the productivity of different regions, social vidualized and extended over places and
groups established ownership over local things that were critical for emergent
territories marked by burial monuments macro-regional trade. Looking first at
and ceremonial gathering places. At burial local systems, settlements often continue
rituals and group ceremonies, local and to have association with inherited property
regional leaders would distinguish them- rights in land. In the Carpathian Basin,
selves and their groups by impressive settlement included a mixture of villages,
ceremonies memorialized in built environ- forts, and tells associated with group
ments. Prestige goods exchange included cemeteries. Each settlement and associated
some early metals and other rare commod- burial area had a degree of permanence
ities, and trade in these objects increased and ceremonial elaboration that materia-
modestly through the Age (Kristiansen & lized the structure of the local corporate
Earle, 2014). As Renfrew (1984) argued, group (Earle & Kristiansen, 2010).
Earleetal.–ThePoliticalEconomyandMetalTradeinBronzeAgeEurope 3
Within each community, relationships 1817). Based on differences in environ-
existed across generations, indicative of ment, resources, skill, know-how, capital
inheritance. What was owned? The land equipment, social organization, market
surrounding settlements and their ceme- access, etc., comparative advantages
teries was most probably associated with emerged reflecting quality or labour value
local corporate groups and further subdi- of goods and services (Rowlands & Ling,
vided along family lines. Critically 2013). The Ricardian ‘law’ assumes the
important, however, ownership came to be existence of an integrated economic
extended over key resources linked to system, but such systems are, in fact, not
metal trade, especially the river routes. universal. They arose in the past, and
Although burials were fairly uniform in threshold factors apparently emerged
content, a small percentage of burials during the BA that created the compara-
(about 5 per cent) was associated with tive advantage of different regions and
metal wealth (Vicze, 2011), probably encouraged the development of macro-
indicative of emergent stratification. regional trade. Thus, comparative advan-
As illustrated by settlements in Scandi- tage relates to modes of production in at
navia, Atlantic Europe developed a new least two different ways. It defines the
pattern of farms and barrows. This land- horizontal relations between regions and
scape probably materialized a new the vertical relations within societies.
property system based on farms with Traded commodities in BA Europe
larger and more long-lasting buildings. included copper, tin, gold, silver, amber,
These houses often replaced each other in wool, hides, textiles, furs, salt, shells, ivory,
the same location, suggesting inheritance glass, and jet, each giving uneven com-
across generations. Associated with farms parative advantages to different regions
were barrow cemeteries (Holst et al., (Figure 1). For example, the Baltic amber,
2013). Each barrow marked a single (or furs, and hides may have constituted
occasional double) primary interment. important components of a Nordic com-
Barrows were often constructed along a parative advantage. The Alpine region
ridge, and secondary burials were added. could have focussed on copper and salt,
The burial and housing patterns seem to and the Carpathians on precious metals,
emphasize family lines probably associated copper, and wool. In Western Europe, the
with inheritance of land and perhaps title. British Isles could have specialized in sup-
Ownership was, however, not simply over plying tin, copper, and perhaps also gold;
subsistence lands, but included control Spain, copper and silver, and maybe also
over lands that produced local exports tin; Sardinia, copper and silver. In the
(Earle, 2002). Distinguishing the individ- eastern Mediterranean, Cyprus emerged in
ual, burials contained personal metal the second millennium cal BC as a major
weapons and finery obtained through producer of high-quality copper and a
trade; wealth was also deposited in hoards, possible market place for tin imported
probably indicating distinction. Across from Asia (Stöllner et al., 2011). On
Scandinavia, the amount of wealth in present evidence, while copper was
burials and between regions was strikingly smelted in the second millennium BC in
differentiated (Earle & Kristiansen, 2010). various places across Europe, tin could
An integrating system of trade that only have been obtained from the far west
stretched across Europe created the com- of Europe (Cornwall and western Iberia),
parative advantage of one region over or from western Asia (Iran, Kazakhstan,
another for export products (Ricardo, and other localities in this region). There
4 EuropeanJournalofArchaeology0(0)2015
Figure 1. Schematic overview of the comparative advantages of the different regions of BA Europe
proposedhere.
are also tin ores in Central Europe in the METAL DEPOSITS AND BRONZE AGE
Erzgebirge, but so far no evidence of BA COMMODITY-BASED TRADE: REVIEW OF
exploitation exists (Haustein et al., 2010). THE EVIDENCE
We believe that trade in copper and tin,
for the ubiquitous bronze inventory of the In various European regions, deposits of
BA, created the underlying conditions that metals were extracted and used in the BA:
drew in trade in other commodities and gold, copper, lead, silver, and tin. The dis-
created a vast, integrated trading system. tribution of rich ore deposits, their ease of
Earleetal.–ThePoliticalEconomyandMetalTradeinBronzeAgeEurope 5
access, know-how of smelting, as well as one another (Rohl & Needham, 1998;
accessibility to trade routes together Ottaway & Roberts, 2008; Timberlake,
created regional comparative advantages. 2009; Pernicka, 2010; Jung & Mehofer,
As metal use increased, long-distance 2013; Ling et al., 2014).
trading networks formed. We start with In the eastern Mediterranean, third mil-
the underlying pattern of extraction of lennium BC copper smelting sites were
copper and tin to understand the econ- found on Kythnos in the Cyclades (Stos-
omic differentiation of source regions Gale, 1989) and on Crete (Betancourt,
(Figure 2). 2006). Although no evidence exist for who
Although copper ores are found in controlled copper extraction in the
many European regions, not all of them Cyclades, the palaces on Crete were prob-
were exploited in the BA. In the second ably in control of the metal supplies. In
millennium BC, large amounts of copper the second millennium BC, Cyprus was a
were extracted, for example, in Cyprus, major centre of copper production. The
the Alps, the Iberian Peninsula, the copper was smelted in the mountains, as is
British Isles, and Sardinia (Stos-Gale indicated by numerous slag heaps, but
et al., 1998; Hunt-Ortiz, 2003; Höppner trade in copper (and possibly imported
et al., 2005; Lo Schiavo et al., 2005; Per- tin) was likely organized and controlled by
nicka, 2010; O’Brien, 2014). Recent coastal towns (Kassianidou, 2013).
provenance studies suggest that periodical The Iberian Peninsula is another large
shifts took place in regional production of BA producer of copper in the Mediterra-
copper as major supply zones succeeded nean, and mines are found both in the
Figure 2. Map showing the major copper, tin, and silver deposits in Europe and the mining areas
mentionedinthetext.
6 EuropeanJournalofArchaeology0(0)2015
south, for example, in the Sierra Morena beginning of the BA and that the use of
(Hunt-Ortiz, 2003), and in the north, for bronze became prevalent in the manufac-
example, in the Asturias on the Atlantic ture of weapon and tool types during the
Fringe (Huelga-Suarez et al., 2014). course of the second millennium cal BC
While fortified sites may have played a (O’Brien, 1999; Pare, 2000; Butler, 2009),
role in distributing metals during the the lower estimates seem unlikely. In
Argaric period, copper extraction was terms of higher assessments, a discrepancy
probably carried out in the mountains; exists between estimated production
however, control by local elites is not output and the amount of contemporary
apparent (Lull et al., 2014). metalwork that has been found (O’Brien,
Early on, many occurrences of copper in 2014), although it must be expected that
the Alpine region were exploited, but only only a fraction of bronze objects has been
a few appear to have dominated. recovered (Taylor, 1999). Based on metal-
Large-scale copper mining took place in work found in graves and hoards coupled
Mitterberg, Austria, probably providing with demographic figures, northern
metal to a large supply region including Central Europe and southern Scandinavia
the Carpathian Basin via the Danube had an estimated yearly metal consump-
(Niederschlag et al., 2003; Krause, 2009; tion of c. 2.5–4 tonnes (cf. Kristiansen,
Pernicka, 2010). Although the abundant 1985; Rassmann, 2011; Holst et al.,
and proficient metalwork in the Car- 2013).
pathian Basin might suggest local These estimates seem much too low for
extraction (Liversage, 1994), at present no the Eastern Mediterranean, considering
conclusive evidence exists for BA copper that the ship of Uluburun dated to the
mining there (Bartelheim, 2009; Boroffka, fourteenth century cal BC sank off the
2009), although copper, gold, and silver coast of southwestern Turkey carrying 10
might have been extracted (see Drews & tonnes of Cypriot copper and 2 tonnes of
Pernicka, 2011; Stos-Gale, 2014). In the tin (Pulak, 1998). The Mycenaean tablets
UK and Ireland, copper mines operated and Near Eastern archives often recorded
first and foremost from 2200 to 1700 cal substantial metal supplies. For example,
BC and into the Middle Bronze Age one tablet from LBA (Late Bronze Age)
(MBA), even if some remained active Knossos recorded sixty copper ingots
throughout the BA (Timberlake, 2009). weighing 1562kg from the palace store-
From 1400 cal BC onwards, lead isotope rooms (Michailidou, 2001). Dated to Late
evidence suggests an influx of copper to Minoan IA (sixteenth century cal BC)1,
the British Isles from the western Medi- the cache of ox-hide ingots in the Aya
terranean (Rohl & Needham, 1998: 182; Triadha palace on Crete weighed over a
cf. Needham et al., 2013). half-tonne. Throughout the LBA, a steady
Assessments of the scale of BA copper supply of copper (and tin) existed in the
production vary widely, from ten or more Aegean, some from local sources (Lavrion),
tonnes annually for the Pongau- some from Cyprus, and small amounts
Mitterberg region in Austria (Zschocke & from more distant sources (Stos-Gale,
Preuschen, 1932; Eibner, 1993) to a total
production estimate for all known BA
1LateMinoanIAistherightnomenclature;RomannumeralI
mines in Britain and Ireland of just over
and capital A indicating that it is the first sub-phase of the
50 tonnes (Timberlake, 2009; cf. O’Brien, Late Minoan chronology (cf. Manning, S. 2010. Chronology
2014). Given that metal rapidly replaced andTerminology.In:E.Cline,ed.TheOxfordHandbookof
theBronzeAgeAegean.Oxford:OxfordUniversityPress,pp.
stone for the making of axes at the 11-28).
Earleetal.–ThePoliticalEconomyandMetalTradeinBronzeAgeEurope 7
2000: 65). The large deposition of bronze production was the first crucial step
in Aegean graves shows that no necessity towards permanent division of labour and
existed to reuse metal. These metal figures a market economy. In this paper, we argue
should be seen as absolute minima as they that this is true only in general terms,
do not consider tool wear and tear or because the emerging ‘international’
normal accidental losses. Lead isotope and (macro-regional) system of trade in the
elemental analysis furthermore indicate BA became increasingly based on the
that large-scale metal recycling was unli- comparative advantage of commodity pro-
kely (cf. Jung & Mehofer, 2013; Ling ducers in different regions. Each
et al., 2014; Melheim, 2015a). Copper commodity can be described as a chain of
was apparently already an important com- producers with differential access to
modity by the Early Bronze Age (EBA) materials and knowledge and trade with
(cf. Pare, 2000). the potential for extraction from the new
Tin deposits in Europe are much less BA political economy.
common than copper. Presently, circum- We conclude that during the BA, fairly
stantial evidence exists for BA exploitation large-scale production and consumption of
of tin deposits in Britain (Penhallurick, metal across Europe created regional com-
1986: 168–221; Rohl & Needham, 1998; parative advantages and a corresponding
Harding, 2000: 201; Timberlake, 2009) network of trade, probably of substantial
and in Spain (Hunt-Ortiz, 2003). Some volume. The gearing up of amber, wool,
copper–tin slag on the Iberian Peninsula and other production for export allowed
also suggests a co-smelting of copper and many regions to participate in what
tin for bronze (Gómez Ramos, 1999). In became an integrated trading system.
the eastern Mediterranean, tin-bronzes
occur early in the third millennium BC,
for example, during the Early Minoan I–II COMMODITY CHAINS: REVIEW OF THE
on Crete (Stos-Gale, 2001; Gale & Stos- EVIDENCE
Gale, 2007). Tin used in the Aegean was
probably obtained from Asian or Anato- A commodity chain involves the linkages
lian sources (Yener et al., 1989). among resource extraction, processing,
Although tin was produced separately, fabrication, transportation, exchange, and
it could be traded with copper, as docu- consumption for a particular product. For
mented by fourteenth- and long-distance trade in regionally special-
thirteenth-century BC cargoes from two ized goods, radically longer and more
eastern Mediterranean shipwrecks: Ulu- complex commodity chains emerged and
burun and Gelidonya, both of which became interdependent. Bottlenecks are
carried copper ingots from Cypriot ores constriction points in commodity chains,
and ingots of tin from quite different, but which offer the opportunity to limit access
so far unidentified sources (Gale & Stos- by creating ownershipover resources, tech-
Gale, 2005; Stos, 2009). nologies, or knowledge (Earle, 2002). We
Although copper and other valuable discuss how bottlenecks emerged in BA
ores occur in many places, the ability and metal flows to offer emerging elites oppor-
skill to extract the metal differed from tunities to extract surpluses in the new
region to region. For example, the people political economy (Figure 3).
of modern Sweden and Norway imported The first step in commodity chains for
copper during the BA despite local depos- metal is mining and extraction of metal
its. According to Childe (1930), metal from ores. Mining and copper smelting
8 EuropeanJournalofArchaeology0(0)2015
Figure 3. Modelofinterplaybetweenbottlenecks(constrictionpoints) andregionalresources(compara-
tive advantages). BA elites benefited from controlling the bottlenecks of commodity chains: know-how
(smelting and metalworking), transportation (routes, means of transportation, and defence), and local
exchange.
activities were not necessary under elite undifferentiated (Shennan, 1995; Kienlin
control or associated with development of & Stöllner, 2009). Even in the Mitterberg
unusual social complexity. Sources could area with its substantial lodes, evidence is
have been open assets, owned by local lacking for elite control. Although sugges-
groups, or by miners and metallurgists tive of a property system, fortified mining
themselves, or perhaps even by traders. On settlements, like St Veit Klinglberg in the
the other hand, in the Aegean during the Salzach Valley, were small, apparently
LBA, copper extraction seems to be getting ore from many lodes (Shennan,
limited to the Lavrion mines in Attica 1998; Stöllner, 2010, 2012). Only when
(Gale et al., 2009), which could have been production became large-scale did control
under supervision by Mycenaean palaces. over mining offer an effective bottleneck.
Lead isotope analysis of several thousand Copper smelting in the BA required
copper-based artefacts from the Mediter- highly specialized knowledge that might
ranean show that copper (as well as lead have been a closely guarded secret, and
and silver) from Lavrion predominates smelting may therefore have provided a
amongst BA Aegean metals; however, bottleneck in the commodity chain.
metals from these sources are rarely found The second potential bottleneck was
elsewhere (Stos-Gale, 2000). The leading limited alternative transport routes for the
role of the Mycenaean palaces in metal metals and other commodities that con-
trade is visible in the inventory of the stricted flows. Early in the BA, Bell
shaft graves in Mycenae, where a large Beaker social groups appeared to have
amount of imported gold was deposited established water-based trade for metal
together with silver vessels made locally, and other commodities (Cunliffe, 2008;
but from silver most likely imported from Pilar, 2008; Heyd, 2013), but multiple
Transylvania (Stos-Gale, 2014). alternative routes of trade at this time
In the Alps during the early second mil- probably limited potential bottlenecks.
lennium cal BC, no dominant mining Found along the Atlantic fringe from
centre existed, so the copper production Spain to Denmark, in the west Mediterra-
did not result in a local advantage of one nean and east to Sicily, and along the
group over others, and the society around rivers deep into central Europe, Bell
the Alpine mines remained largely Beaker settlements are associated with
Earleetal.–ThePoliticalEconomyandMetalTradeinBronzeAgeEurope 9
some of the earliest metal objects and provided particularly effective, high-
metalworking (Pilar, 2008; Heyd, 2013). volume trade routes, settled groups could
Recent research indicates that at least have constricted flows and extracted pay-
two major BA systems of metal flow seem ments for safe passage. Childe (1929)
to have connected northern and southern originally stressed the importance of rivers,
Europe: (1) riverine routes (Central Euro- especially the Danube, as transportation
pean), and (2) maritime routes (Atlantic/ routes for commodities. Along the
Mediterranean) (Ling et al., 2014). Inter- Danube’s bluffs in Hungary and other
action between these flows created more major waterways, chains of fortified tells
or less integrated trade throughout arose in the EBA and MBA (Gogâltan,
Europe. Each set of routes had rather dis- 2008; Uhnér, 2010; Szeverényi & Kulcsár,
tinct bottlenecks that would have served 2012), and each fortified settlement prob-
differently for emergent social hierarchies ably extended property rights over the
(Figure 4). rivers. Along the Hungarian rivers and
The riverine routes channelled metals their immediate hinterland, metal finds
and other commodities along waterways occur in major hoards (Mozsolics, 1967;
between north, central, and southern Hansen, 2005). Similarly contemporary
Europe. In situations where large rivers fortified settlements and hoards occurred
Figure 4. A hypothetical outline of European copper and tin routes supplying Scandinavia during the
BA. Areas marked in black denote copper bearing regions, matching metal signatures in Scandinavian
bronze artefacts (Ling et al. 2014). The tin bearing region in Cornwall is marked with silver, while
the silver arrows signify an eastern influx of tin. Note: the arrows and directions on this map should
not be read literary as the only routes in operation between southern and northern Europe during the
BA.Itisamodelthatindicatesdirectionalflows.
10 EuropeanJournalofArchaeology0(0)2015
next to the waterways further north in Slo- then later expanded and used by Scandi-
vakia (Bátora, 2009). Clusters of EBA navian maritime chiefdoms from c. 1600
hoards also existed at mouths of Alpine cal BC (Rowlands & Ling, 2013).
rivers (Krause & Pernicka, 1998; Krause, Although evidence for trade along the
2003), suggesting that trans-shipment maritime routes remains preliminary,
places created effective bottlenecks. We much of the metal was probably moved by
propose that the fortified tells along the sea to Scandinavia via the British Isles
Danube and other transport routes acted (Ling et al., 2014). Nordic bronze swords
as central places for small-scale chiefdoms, and other MBA (1500–1300 cal BC) arte-
as exemplified in the Benta Valley, facts share isotopic signatures with British
Hungary (Earle & Kristiansen, 2010). swords that in turn seem to be consistent
Similar chiefdoms probably arose at with copper ores from western Mediterra-
mountain passes, river crossings, and other nean. Tin is key to understanding the
constriction points, where moving metal Atlantic network in the BA, and a tin
and other wealth would then have required ingot found in Sweden has lead isotope
payments for safe passage through each ratios consistent with Cornwall ores (Ling
local polity. et al., 2014). Western Mediterranean
Copper from the Alpine region moved copper could have been transported either
to Scandinavia probably following the via the south coast of France through the
rivers Oder, Elbe, and Vistula to the Garonne axis to the French Atlantic coast
shores of the Baltic Sea and transhipped and northwards to Brittany, the British
across the Baltic to Scandinavia. Addition- Isles, and Scandinavia, or via southern
ally, copper from the eastern Spain and Portugal and Galicia north-
Mediterranean (Cyprus) may have been wards across the Celtic Sea to Brittany,
transported northwards through Eastern the British Isles, and Scandinavia.
Europe via the Carpathian Basin, and For maritime connections, such as
some of the metal from the western Medi- between the British Isles and Scandinavia,
terranean may have moved through a currents make sea transport more reliable
central European overland/riverine system and lower cost. Sea currents connecting
(Ling et al., 2014). Geo-chemical analyses the British Isles and western Scandinavia
(Pernicka, 2010) indicate that some metal were probably used already in the Neo-
found in the Carpathian Basin had sources lithic (Figure 5). Judging from find
in the Alps, probably coming by overland distributions, Bell Beaker maritime ven-
and river routes to the Danube and its tures followed the Atlantic fringe, a trail
tributaries. that was crucial earlier for the spread of
When analysing water-based transport, megaliths and stone-axe trade (Cunliffe,
the number of alternative routes is critical 2001; Pilar, 2008). Maritime groups evi-
to define potential bottlenecks. The more dently used sea currents to minimize costs;
options (of equivalent cost) that were the currents from the British Isles to
available, the less constricted was a bottle- Sweden’s west coast hit the densest area of
neck. The western maritime routes figurative rock art and monumental burial
channelled metals in two directions from cairns that document trading (see later
the copper mines of Spain and Sardinia in discussion).
the south and copper and tin from British With maritime routes, bottlenecks were
Isles and Ireland. These routes were prob- quite different from riverine routes.
ably established by Maritime Bell Beaker Open-sea trade is almost uncontrollable,
groups in the third millennium BC and because routes could easily shift to avoid