Were your family 'slave owners'?
27 February 2013 Last updated at 09:53 GMT
The most detailed picture of how the abolition of slavery worked in this country is available online from today: research showing the pattern of slave ownership by people in this country.
It has been compiled by historians at UCL in London and it shows how, after abolition in 1833, 46,000 claims for compensation were made by people who had lost "property" namely the slaves they owned.
The compensation cost the taxpayer £20m.
The database also allows individuals to trace parts of their family history that may have been obscure.
Prof Catherine Hall, project leader in the department of British social and cultural history at UCL, told Today presenter James Naughtie that the "information is now online and available for free".
"It is individuals all over the country in the most unlikely places" that were involved, she explained.
You can find out more about the Legacies of British Slave-ownership study and search the database on the UCL website.
First broadcast on BBC Radio 4's Today programme on Wednesday 27 February 2013.