Mapping Legacies of British Slave-Ownership

The Centre for the Study of the Legacies of British Slave-Ownership at University College of London is a vital resource in Britain’s often unwilling attempts to address its own role in the history of slavery.

In 1833 Parliament finally abolished slavery in the British Caribbean, Mauritius and the Cape. The slave trade had been abolished in 1807, but it had taken another 26 years to effect the emancipation of the enslaved. In place of slavery, however, the negotiated settlement established a system of apprenticeship, tying the newly freed men and women into another form of unfree labour for fixed terms. It also granted £20 million in compensation, to be paid by British taxpayers to the former slave-owners. This was the largest state pay-out until the bail-out of the banks in 2008. This colossal debt was only finally paid off in 2015.

The bureacratic processing of compensation applications left behind a wealth of data. This has enabled historians at the Centre for the Study of the Legacies of British Slave-Ownership (LBS) to gain detailed insights into some of the ways in which slave-ownership permeated every level of British society. It was by no means only the rich and powerful implicated in slavery (although they could do most to ensure its continuation); the slave system was almost inseperable from the entire economy.

One of the most immediately accessible aspects of the work at LBS consists of a series of maps. In particular, there is a map of the UK showing addresses of those who received compensation for the ‘loss’ of what was deemed to be their ‘property’ – i.e., the human lives of enslaved people. There are currently over five thousand addresses in the LBS database, of which over three thousand have been mapped.

The men, women and children subjected to the brutalities of the system, the enslaved people themselves, were never compensated; in fact, as historian David Olusoga has written, descendents of enslaved people were, for generations, actually paying taxes to compensate those who enslaved their ancestors.

We emailed Rachel Lang, administrator and researcher at the Centre for the Study of the Legacies of British Slave-Ownership, who works primarily on Jamaican data and maps. She was kind enough to answer our questions.


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Firstly, an obvious question: why was this information hidden for so long? And how did UCL find out about it and found the centre?

There are hundreds of boxes of documents at the National Archives in London generated by the bureaucratic process of allocating and dispensing the slave compensation money. Nick Draper came across them when he was researching a different subject at the archives. He realised the boxes required further study and that the information in them should be made public so he based his PhD on the records. The Centre for the Study of the Legacies of British Slave-Ownership (LBS) began from the collection of data Nick made for his PhD.

I don’t think there was a ‘cover up’ of information specifically. In terms of why it took so long for the slave compensation process to become a matter of public knowledge (rather than just academic knowledge), in our national memory the importance of British people in the abolitionist movement has long eclipsed the importance of Britain’s vested interest in the slavery business. Abolition is the story we have preferred to tell ourselves over the centuries. A focus on slave compensation payments undermines the idea of Britons seeking liberty on humanitarian grounds, even though many abolitionists were in favour of the payment of compensation in part because it made abolition more likely.

The project was begun in 2009. In what year did the map-making component begin? And what year was the first map completed?

The map-making began in maybe 2012. This was before any of our data went online. Someone emailed us saying they were creating a walking tour of Bloomsbury and could we help them with the addresses of slave-owners? But there were so many slave-owners living in the area in the late 18th, early 19th centuries that it made more sense to plot them on a map rather than to just send a long list. Over the years, we expanded the Bloomsbury map to cover the whole of Britain and added addresses in Europe and Australasia.

The Caribbean maps began with a conversation between LBS and the National Library of Scotland (NLS). We found the NLS’s georeferenced Robertson map of Jamaica online and asked if we could use it on our website as a different way of representing our Jamaican data. They were very helpful. Then we decided to do some georeferencing ourselves and added the Barbados and Grenada maps.

Legacies of British Slave-ownership

How do the maps help to make clear to a modern audience the pervasive reality of slave-ownership? What is it about a map that helps bring histories home to people – in ways that perhaps articles and artefacts, statistics, infographics, even vivid personal stories somehow do not?

One thing that’s striking about the LBS map of Britain is that slave-owners were everywhere – even though we’ve only added just over half of our address data to the map so far, and are constantly adding more slave-owners and more addresses to our data as a whole. This counteracts the idea that slave compensation was only about rich people, or only about people in London, Liverpool, Bristol and Glasgow.

You can zoom in to wherever interests you most, move around as you choose. We can add a lot more information to a map and make it immediately visible whereas a database search form will only retrieve the specific information you asked for. We are used to clicking on icons and pursing our own agenda. We know our maps are used particularly in schools, and particularly in primary schools, because children work instinctively with graphical interfaces – they use them all the time on ipads.

The telling of the stories of Britain and slavery is very different to the telling of the stories of the US and slavery, for example, because in Britain we have promulgated the idea that slavery is something that happened ‘over there’ and not ‘over here’. The map of Britain is an attempt to undermine the way we have distanced ourselves from the horrors of colonial slavery; this is the history of all of us, black and white.

Most importantly, the maps provide a ‘way in’ to our data. If you are familiar with a place but not with its history then you can use the maps to begin to access the history.

Legacies of British Slave-ownership

Aesthetically, there is a clear difference between the maps. Those of Jamaica, Barbados and Grenada begin with colonial-era survey maps from the 18th and 19th centuries before zooming in to modern satellite images. That of Britain, however, shows the addresses of slave-owners on OpenStreetMap. Jamaica, Barbados and Grenada therefore feel like maps of a historical moment, while that of Britain perhaps suggests how the enduring effects of slave-ownership continue to be felt today. But that’s just my reading… what was the intended effect behind this difference in approach? Or was it the result of different data and therefore different map-making processes?

That was the intended effect. There is a practical consideration as well, in that many of the estates in our early 19th century data aren’t labelled as such in modern maps whereas in most large cities the street layouts that had been platted by c. 1850 have remained fairly consistent. Streets have often been renumbered but less often renamed.

One consideration which applied particularly to the first Caribbean map we used, the Robertson map of Jamaica, is the early 19th century map as a piece of social history with its own story to tell. Robertson spent three years creating his map. He was very well-paid for his work. In his wanderings and measurements around the island, he found a population of c. 350,000 enslaved people living in an extraordinarily brutal system of social, physical, mental control, but aside from a couple of villages, their presence does not appear on the map. The enslaved people are represented (in their absence) by the sugar mills, slave society is plotted essentially as units of industrial production.

You mention James Robertson, the Shetlander who mapped Jamaica and Aberdeenshire. What role did mapping play in imposing and perpetuating slavery?

Early deeds are complicated and demarcate boundaries by listing who owned the properties to the north, south, east and west. Maps would have been useful! Large tracts of land were distributed by the government with varied conditions attached and sometimes reverted back to the crown. There are early maps of plantations showing land-use on different properties – the maps were sent back to Britain for absentee owners. B.W. Higman’s book Jamaica Surveyed could tell you a lot more about this; I’d like to read it again myself but the libraries are shut.

If mapping is about knowledge and power, what new powers do you hope will emerge from UCL’s mapping project?

We hope it will make our data more accessible and that people will use the maps to find out more for themselves..

Legacies of British Slave-ownership

It’s often important to ask about what gets omitted from maps. For example, David Olusoga’s two-part documentary for the BBC in 2015, Britain’s Forgotten Slave Owners, refers to several institutions that benefitted from slavery. The LBS map of Britain refers only to the addresses of private individuals. Is this a decision made by the UCL team or a result of the way the applications for compensation were compiled? Were institutions involved in owning people as slaves or was it only private individuals?

Mercantile partnerships were involved in the slave compensation process and in the ownership of estates, often as a result of unpaid mortgages or other failed credit arrangements. Creating a sugar estate took a lot of capital and, especially up till the mid-18th century, there were often complicated and convoluted partnerships between planters owning different proportions of different estates. But slave compensation was awarded to individuals, not companies – the senior partners in banks would appear as slave-owners rather than the organisation itself. The West India market wasn’t developed to the extent that you could buy shares in a company. The most stunning omission from the maps is slave society.

If you were to create a future map, what might you look to include? Could the legacies, for example, be mapped somehow?

We would very much like to map the physical legacies and plan to add a map of St Kitts by the end of this year. We tried to automate the process of adding nodes to the LBS map of Britain but found this introduced too many mistakes so now we search for each address using OpenStreetMap. This is time-consuming. Our main aim moving forward is to connect nodes on the Caribbean maps to pages from the slave registers, so our maps will be of enslaved people not only of slave-owners.

The documents refer to addresses in 1833. What challenges did you face mapping historical addresses onto modern maps?

The renumbering of streets caused us a lot of problems, so we have generally plotted whole streets rather than specific buildings. Another problem is that we have different levels of detail in our address data – so we may know someone lived at 87 Duke Street, Liverpool, or we may know only that someone was Liverpool-based. We have added a lot of country houses to OpenStreetMap and then imported them into our database. We have also added people at pre-1833 addresses so we now have different times represented on the British map. There’s so much we’d like to do but the amount of time we have available to spend on mapping is very limited.

In light of Black Lives Matter there are growing calls for people in Britain to face up to the nation’s role in the history of slavery and its continuing influence on today’s social, political and economic structures. 11 years on from its formation in 2009, what role is the centre playing in national conversations today, and how are the maps aiding that role?

There are many historians (including those at LBS) involved in writing reparative history. We are keen that data and research is made as widely available and as easy to access as possible, that this kind of work isn’t confined to universities. I think the role of LBS is best summed up in a statement we released in June.


For more information on UCL’s Centre for the Study of the Legacies of British Slave-Ownership, visit the website.

Links to the interactive maps here:


This is part of ROOT MAPPING, a section of The Learned Pig devoted to exploring which maps might help us live with a clear sense of where we are. ROOT MAPPING is conceived and edited by Melanie Viets.


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Launched in November 2013, The Learned Pig is an online arts magazine with a love for plants and animals. Our thinking has grown out of our engagement with landscape aesthetics and environmental ethics and these days we try to bring together multiple perspectives on bodies and places, interspecies interactions, and alternative conceptions of that which has rather too frequently been defined as “nature” or “the animal”.