Close to four million records documenting enslaved people across 20 former British colonies — spanning territories including Jamaica, Barbados, Mauritius, and the Cape of Good Hope — have been made freely searchable online for the first time through a partnership between genealogy platform Ancestry and University College London's Centre for the Study of the Legacies of British Slavery. The collection, drawn from roughly 300,000 pages of government registers compiled between 1813 and 1840, includes names, ages, physical descriptions, family relationships, and details of births, deaths, and ownership transfers — records originally created by British authorities to monitor enslaved populations following the 1807 abolition of the transatlantic slave trade. Researchers say the archive represents the most systematic surviving documentary record of British colonial enslavement and could allow millions of descendants across the African-Caribbean and broader African diaspora to trace family histories that have long been difficult or impossible to access.