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Mapping precolonial African agricultural systems
Paper presented at 3rd European Conference on African Studies, Leipzig, 4 to 7 June 2009
Panel: Historical Roots of Poverty and Well-Being in African Countries
Mats Widgren
Department of Human Geography
Stockholm University
mats.widgren@humangeo.su.se
Do not quote ! BUT PLEASE SEND COMMENTS TO THE AUTHOR!!!
Background - a global map of the history of agricultural systems
It is increasingly recognised that early developments in land use had implications for the
global climatic system. Especially following the article by Ruddiman (2003) ‘The
Anthropogenic Greenhouse era began thousands of years ago’, reconstructions of past land
use has become an important topic in the rapidly growing research field on global climate
change studies. Historical geographers have been slow in responding to this new demand of a
global synthesis. Hence, many articles on climate change and historical land use, are based on
superficial data from historical atlases or back-projections of 20
th
century land use. These
reconstructions therefore more reflect Eurocentric assumptions among climate modellers, than
they reflect the current state of research on global landscape history in archaeology, history
and historical geography. Especially the understanding of pre-Columbian farming landscapes
in the Americas has developed rapidly during the last decades. For Africa, there is also a
burgeoning research on pre-colonial farming systems and landscapes.
One of example of a highly quoted set of data on the historical land use is the
reconstruction by Klein Goldewijk (2001). For mainland Africa at 1700 it shows almost no
cropland south of 10 degrees south (Angola. Zambia, Mozambique, Namibia, Zimbabwe,
Botswana, South Africa).
1
A more recent attempt by Pongratz et al. (2008) based on the same
approach methods is more successful in giving a fair representation of a probable precolonial
distribution of agriculture in Africa at a continental scale, but fails utterly for the Americas.
These data sets, based on simple back-casting from recent cropland distributions, are easily
accessible in digital format are widely used by climate modellers.
On the other hand, in the rapidly growing literature on the origin of globalisation, which
attempts to answer questions similar to those of this panel, there is a real lack of up-dated
maps of the distribution of and the characteristics of agricultural systems prior to Columbus in
different parts of the world. Such maps would potentially give the empirical basis to inform
the different attempts in answering some of these basic questions in macrohistory, on where
surplus production was possible. These may be raised within popular science (Diamond
1997), economics (Acemoglu et al. 2005), geography (Blaut 1993) or “geohistoire”
(Grataloup 2007). Basic questions are: Why did Western Europe take the lead? Why is Africa
lagging behind? Was Africa as advanced as Europe in the 16th century.
In many of these studies the 15
th
century is taken as a starting point. But the basic data,
on productive capacity and farming structure and hence the “degree of development” are
mainly lacking. It is indicative that Christian Grataloup (2007) in his argument, why Western
1
A similar, and also much qouted reconstruction was been published by Rammankutty and Foley (1999)
Europe and US became the main axis of control, bases his understanding on a reading from
Braudel (1979), who quotes an American ethnologist, Hewes, who in 1954 published a map
of world agriculture in the 15
th
century. In Braudels and Grataloups interpretation the
agricultural systems are presented as different stages in an evolutionary chain of development.
The basic problem with the idea about stages of development is that it, for instance,
categorises agriculture without plough as a more primitive system, without trying to
understand this system and its rationality. As comes clearly out from Grataloups use of
Braudel/Hewes such an understanding supports ideas of a modernity emerging in Western
Europe and later spreading all over the world. Since the heyday of such evolutionistic ideas
the field has advanced to a much more sophisticated understanding of the social and gender
aspects in the broad classification of agrarian societies (Bray 1997, Blumberg 2004).
The work that I will present here forms part of small, interdisciplinary project among
historical geographers and economic historians in Sweden and the US.
2
Our aim, is to produce
a series of global maps of agriculture in the late 18th century, the late 15th century and
possible in the 12th or 11th century, based on the most recent empirical data. The map will be
done in scale and detail comparable to the much quoted map of the major agricultural region
of the world published by Whittlesey in 1936. The series of maps will not go into detail but at
a general level represent the state of research in global agrarian history and historical
geography. The project is thus not based on new research, but aims at compiling existing
literature to achieve a better guesswork than the Eurocentric maps that are now circulated,
widely used and quoted.
Agrarian history in Africa
My part of that global project, is to produce a series of maps of African agricultural
landscapes. This has proven more difficult than foreseen. For the Eurasian continent there is
much more research and at the same time a stronger degree of continuity of agrarian
landscapes. For the Americas, the discontinuity and the demographic collapse following the
Columbian encounter has, on he other hand, in some places left a remarkably well preserved
archaeological material, which has in recent decades been researched by archaeologists,
palaeo-ecologists and historical geographers. This has also been synthesised in a series of
volumes (Doolittle 2000, Denevan 2001, Whitmore and Turner 2001) and in a popular
account, which also summarised the evidence in map form (Mann 2005).
While in Africa there exists some documented examples of agricultural areas that were
abandoned as a direct or indirect result of European colonialism, such disruptions can hardly
be seen as the norm or are at least not documented to a larger extent. The evidence of pre-
colonial agriculture can therefore note be found so much in the archaeological material in the
form of abandoned landscapes, but rather in documentary and oral history.
But much of the historical literature on Africa, opens only a few avenues to a better
understanding of agricultural systems. Much writing about pre-colonial agriculture in Africa,
still suffers from the “ethnopresence” genre. While reading works by historians, and also
archaeologists, it is often difficult, when it comes to agrarian systems, to discern between on
the one hand assumptions based on ethnographic material and on the other conclusions based
on oral or written history or on archaeological results. This confusion of 20th century
ethnographically documented African farming practices with what was there before, and,
2
Bill Dolittle (University of Texas-Austin), Ulf Jonsson (Stockholm University), Janken Myrdal (Swedish
University of Agricultural Sciences), Mats Widgren (Stockholm University), Bill Woods (University of Kansas)
along the same track, the attribution of certain farming practices to certain tribes was of
course common in the older literature (see e.g. Beck 1943). But we can now also see that it
did, as Paul Richards has pointed out, to a certain degree also spill over to Marxist analyses of
African agriculture. Richards argued in 1983 that ‘the demographic and ecological processes
subsumed under the category “natural economy” (or alternatively, “precapitalist subsistence
production”) are more plausibly viewed as the products of capitalism and colonialism’
(Richards 1983:1).
An other strand of research towards an ecological history of African agricultural
systems was initiated by Kjekhus for Tanzania, and it opened up for a more varied
understanding of precolonial African agrarian systems, following in the footsteps of
researchers such as Allan (1965) and Miracle (1967). Kjekshus made it likely that, in
Tanzania, a series intensive and advanced agricultural systems were abandoned during the
19
th
century as an effect of the caravan trade and European colonialism (Kjekshus 1977:29-
48). Although Koponen (1988) balanced the understanding of this, the question of Merry
Africa vs. Primitive Africa is still to large degree an unsolved problem, due to the lack of a
detailed analysis of the chronology of agrarian history.
The following work is based on the existing historical and economic historical literature
(mainly in the form of regionally focussed monographs), some interdisciplinary
environmental history projects and more specialised archaeological work. To a smaller extent
paleoecolocial works have been consulted. The work is not yet completed in map form, but I
will in this presentation highlight on some of the spatial processes of change that the map
sequence will be able to highlight.
In this paper, I will focus on four regions or thematic areas, where it previous work has
provided a basis for understanding pre-colonial from a spatial perspective. Since the global
map will focus on three cross-sections in time: AD 1000, AD 1500 and AD 1800 I will in
this presentation also limit myself to what evidence can be gathered for these cross-sections
and for documented changes between them.
South Africa – 1000 – 1800
The expansion of farming in Southern Africa 1000 AD to 1800.
I want to start this presentation by giving you an example of the kind of map that will be close
the final outcome of this project. I have chosen South Africa as an example for two reasons.
One reason is that it provides a clear case where contesting views on the history of settlement
and land use have been politically important and also, to an extent, still plays a role. (I have
encountered scary examples of lack of knowledge of the African farming and settlement
before Europeans in my mail conversations with colleagues in climate science). The other
reason is that, for that precise reason, archaeologists in South Africa already during the
apartheid era were committed to present their results in map form. In this compound map I
have used the data presented by Tim Maggs (Maggs 1976, 1980 and personal
communication). We can see how African farming societies had expanded to the famous Fish
River, already at around 1000 AD. Archaeological registration has shown farming
communities from that time, especially along the south-eastern coastline. By 1800 the
expansive farming communities had more or less reached the limit of the summer rainfall
region and hence areas where cultivation of sorghum was possible. Most of that expansion
was connected to agropastoral societies, where grain cultivation on an extensive basis was
combined with large cattle herds kept elsewhere. But by 1800 a development towards
intensive mixed farming, with terracing and elements of water control, had just started in an
area in the Drakensberg, possibly based on maize cultivation (the area of Bokoni or Marateng:
Delius & Schoeman 2008, Maggs 2008). By that time the introduction of European crops of
rye and wheat also made possible the Boer agrarian expansion in the winter rainfall area of
the Cape– and according to some sources this almost experimental cultivation mainly for self
sustenance covered a larger area than what later came to be consolidated as a commercial
grain farming area.
Islands of intensive (terraced and or irrigated) agriculture 1500 - 1800
The localised occurrence of pre-colonial irrigation and soil-and-water conservation in the
form of terracing has, in Africa, has generally been considered an exception from an assumed
prevailing system of shifting agriculture. In a previous project we investigated and compared
some of the cases mainly in eastern Africa (Widgren & Sutton 2004). The “islands” of
intensive agriculture, were in that work, seen as signs of incipient, but halted, process of
intensification. They witness to the fact, that from the perspective of landscapes, soils and
climate, a development towards a much more intensively cultivated landscape was possible in
eastern Africa. Terracing, mulching, manuring, and irrigation was known and it can be
seriously questioned whether the often quoted environmental problems in Africa were really
the causative factor behind the slower development in Africa, as compared to similar
environments in India.
3
In that work we tried to single out some of the factors leading to intensification and
emphasised the geographical labour division, though institutionalised exchange. Since then
further investigations into other “islands” of intensive agriculture in eastern Africa have been
completed. Daryl Stump has analysed the chronology and function of the abandoned irrigation
system at Engaruka (Stump 2006a, 2006b) and Matthew Davies investigated the history of
furrows in area of the current irrigation among the Pokot in Kenya (Davies 2008, 2009).
Davies has also further developed some of more general conclusions of the driving forces
behind intensification in these cases (Davies forthcoming).
As we can understand this intensification now, it was in all documented cases connected
to a geographical division of labour – in some cases as a direct consequence of the caravan
3
This view was on general level developed by Morgan 1988. He developed his argument, not on the existence of
pockets of intensive agriculture in eastern Africa, but on a comparison of landforms, soils and climate in the
intensively cultivated Tamil Nadu with the sparsely populated eastern Tanzania. See also Gunnel 1997 for a
contrasting view.
trade in the 19
th
century (Baringo, Kenya see Andersson 1988, 1989) and in other cases
through institutionalised exchange within or between ethnical groups (Östberg 2004, Loiske
2004). The relations between, on the one hand trade and exchange, and on the other,
investments in landesque capital has been further elaborated for four contrasting cases in
Tanzania (Håkansson & Widgren 2007).
This approach to explaining localised cases of intensive agriculture was to certain extent
developed as contrast to the approach by Gourou, who emphasised how such localised
occurrences of intensive farming should be understood as the outcome of a siege-like
situation, where slave-raiding or the existence of threats from pastoral groups have acted as a
pressure towards intensification (Gourou 1991). The scrutiny of one of Gourous cases, the
Iraqw of the Mbulu highlands formed the basis for Lowe Börjesons critique of the “siege
hypothesis” (Börjeson 2004).
Areas of intensive and terraced farming in West Africa and the Sahel (based on Froelich
1968, Grove & Sutton 1989, Hale 1964, Lebon 1965)
In connection with this project I have made an attempt at broadening the geographical
base for this discussion and made rapid overview of recent research on similar islands of
intensification in Western Africa and in the Sahel zone. These intensive agrarian systems,
from the Dogon and the Kassena in the west to the Nuba hills (Kordofan) in the east, have
mainly been described as the outcome of the slave raiding from the 15
th
century onwards. In
the old German and French literature they have been described as the remnants of a
paleonegritic culture, who escaped the slave raiding by retreating into inaccessible hills or
refoulés montagnards. While this interpretation is often quoted in literature focusing on the
recent development among these hill farmers, there is surprisingly little historical and
archaeological evidence for the age of the terracing and other farming practices. In two cases I
have encountered a more robust discussion about the dating of terracing. For one area in the
Mandara mountains in the Cameroon MacEachern has shown, based on archaeological
investigations, that the terracing must be seen as having “existed only for some hundreds of
years (MacEachern 2003:321). On the other hand, for the Tangale Waja uplands in Nigeria,
Kleinewillinghöfer has argued, based on linguistic research, that the terracing must have been
a feature on these hills well before the present groups occupied the area (Kleinewillinghöfer
1996).
In the lack of more detailed historical and archaeological studies on the chronology of
terracing and other farming practices associated with this labour intensive agriculture, any
judgement of the situation of these areas in, say 1500, must be conjectural. It seems probable
that in 1500 and well before, many of these hills were indeed settled and farmed. Also, all
evidence points in the direction that they offered some environmental advantages to their
surrounding savanna lowlands. Higher precipitation and, often, good volcanic soils offered
possibilities for those who were ready to embark on a labour intensive agriculture. Terracing,
mulching, manuring and other intensive farming practices might therefore in these areas have
their origin in times well before the slave raiding, although the extent of terracing at that time
can not be established. For the discussion of the role of slave raiding for establishing or
strengthening this intensive farming, the results from eastern Africa may be enlightening. As
has been argued by Östberg and Davies the tendencies between on the one hand a situation of
conflict with neighbouring pastoral groups and on the other a peaceful cooperation and
exchange between agriculturalists and pastoralists, must not be seen as diametrically opposed,
but rather indicative a dialectic relation between cooperation and conflict (Östberg 2004,
Davies forthcoming). Applying these ideas of interpretation to the problem of the “hill
farmers” in West Africa and the Sahel zone, one might suggest a process whereby the slave
raiding accentuated an already existing labour division between groups occupying the hills
and groups in the surrounding savannas.
Intensification in the Congo basin 1500- 1800
In most maps of African agricultural systems a large zone of central and equatorial Africa is
usually characterised as based on shifting agriculture. From the overviews by Allan (1965)
and Miracle (1967) we however know that, throughout that region, extensive forms of shifting
cultivation often coexisted with horticulture close to the settlements. For some of the crops,
there were also variations the form of the forest based shifting cultivation so that a more
labour intensive kind of shifting agriculture, with mounding and composting, is practiced.
With the arrival of the American crops, especially cassava, but also maize, these labour
intensive practices seem to have increased in importance.
Intensification -- mainly based on cassava – along the trade routes in the Congo basin .
Extent of Portuguese trade area by 1830 marked in read (from Vansina 1990:212-213)
For the central parts of the Congo basin Vansina has shown how the arrival of American
crops combined with the expansion of the Portuguese trade led to localised areas of a more
intensive agriculture (Vansina 1990). According to Vansina the demand for foodstuffs to feed
the slave trade led to this intensification, first by slave villages and farms and later on by the
introduction of the new high-yielding American crops. Of special importance was the
manioc/cassava because of its storing capacity. Intensive and labour demanding cultivation of
cassava then developed among the main trade routes and their immediate hinterland. Vansina
is, however, not very precise about the chronology of these processes.
A contrasting view, of the role of trade versus the role of an indigenous agricultural revolution
in the spread of cassava in central Africa, is presented by Achim van Oppen. (1999). He
shows that the remote interior of central Africa took up that cassava cultivation well before it
was accepted at the coast. It was present in the Lunda empire in 16
th
century, and reached the
upper Zambesi in 17
th
century. von Oppen categorises the adoption of cassava in these areas
as an indigenous revolution. He shows how it enabled an increased permanency of fields, and
hence a reduction in the labour for clearing new land. This had effects on the gendered
division of labour, with increased workloads for women in the planting, mounding and
composting and reduced male labour in clearing new lands (Oppen 1999).
The rice expansion 1000-1800
Reproduced from Carney 2003
The development of indigenous rice cultivation in West Africa has recently been the subject
of a series of works by Judith Carney (2001, 2003) and William Hawthorne (2001, 2003). The
wetland rice farming in the Senegal and Middle Niger rivers played an important role for the
food supply for trade and for the Ghana Empire in the 11
th
century. From that area rice
cultivation spread and successively developed into two varieties, one rain-fed type which had
its centre in Guinea, while an irrigated type of rice cultivation, distinct from the inland Niger
type of cultivation, developed on the Senegambian coast. This mangrove cultivation of rice,
involved the clearing of mangroves, the building of dykes, the desalination of large areas of
land and the creation of canals, sluices and dykes. That type of rice farming, which developed
before 1500, was closely connected to the long-handed flat-bladed spade shovel. With its iron
share it made it possible to clear the mangrove forest and expand the cultivation. But as
Hawthorne has shown this type of cultivation was during the 16
th
century restricted to
Mandinge speakers in the Senegambia. Through their control of the trade with Iron they also
controlled the techonologically advanced rice cultivation. With arrival of the Portuguese
traders other groups along the coast were able to the Iron and the paddy rice cultivation spread
southwards during the 17
th
and 18
th
centuries partly and formed an integral part of the slave
trading network. The story of the labour intensive paddy rice cultivation in Western Africa
from the 11
th
to the 19
th
century thus reflects an intricate interplay between the political
economy of the slave trade, ethnic affiliations and an advanced iron-using technology.
Discussion
I have above presented four different examples of precolonial agrarian change in Africa.
These processes of change have been chosen from the perspective that they have a clear
spatial, mappable, aspect. I have thus not entered into this overview with any clear theoretical
approach to growth and intensification. In the cases presented above some can be seen as
clearly related to, and fuelled by the regions involvement in long distance trade. That is the
case for rice expansion in West Africa and for the interpretation that Vansina gives to the
introduction of cassava in the Congo basin. This can be contrasted with many of the islands of
intensive agriculture in the Sahel and in eastern Africa, which were not drawn into long
distance trade, but formed part of networks of institutionalised exchange, and by the
characterisation by von Oppen of the early adoption of cassava in Lunda and in the upper
Zambesi as an indigenous revolution.
The linkage between agrarian intensification and the external trade systems of course
partly reflects the fact that the most evident sources for describing agricultural change
emanate from areas and periods with a European (or Arabic) presence and a written history.
But it is difficult evade a conclusions that the involvement in trade networks was on of the
causative factor for the development of intensive farming and the introduction of farming
practices that enabled surplus production.
Going back to the initially posed question why an “Asian” development not occurred in
Africa it is tempting to go back to some of the maps describing Africas role in the Eurasian
trade networks. In the first millennium AD when many Asian regions had already started a
development towards a landesque-capital intensive and labour intensive farming these regions
were also at the crossroads of several intensive east-westerly trade networks, while Africa to a
large extent seems to have more peripheral in these exchanges. (Beaujard 2007 – see map
below.
After Beaujard 2007: “The Eurasian and African world system from the first to the third
century”
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