One of the busiest slave trade 'hubs' in the 18th and 19th centuries at the height of the British empire, the register contains the names of 99,349 slaves and 5,206 slave owners - an average of 19 slaves to every owner. However the full collection does include several people owning up to 400 slaves.
Of the 99,349 slaves listed, 46,347 were male and 52,982 female: 26,787 were aged ten or under.
Famous living Brits with Barbadian ancestry include former All-Saints member Shaznay Lewis, footballers Ashley Cole and Theo Walcott and newsreader Moira Stewart.
"As few records exist which document the lives of individual slaves, the Former British Colonial Dependencies' Slave Register Collection, 1812-1834, will for many be the only record of their ancestor ever having existed and so represents a vital resource for everyone with or interested in researching slave ancestry," Ancestry.co.uk spokesperson Simon Harper said.
It is hoped the collection will "bridge major historical gaps for many people", Mr Harper added.
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