Who was cast as "Uncle Tom"?

Years ago, when I first researched Black Victorians,  I trawled through the catalogues of the annual Royal Academy exhibitions for  titles that suggested 'Black' sitters or subjects. ['Head of  a Negro'  and 'Othello' were quite frequent.]  I swiftly found that after the publication in 1852 of Harriet Beecher Stowe's  Abolitionist novel Uncle Tom's Cabin, scenes from the story became suddenly popular.
Furnished with the artist's name, further research might lead to the painting, although in all too many cases the proliferation of minor artists in the period meant that both they and their works languished in oblivion. Even for better-established painters, very often works are unlocated, unrecorded anywhere since their first appearance.  So it was gratifying when, shown the canvas here, by Thomas Uwins:

and deciding that it probably depicted the enslaved 'Uncle Tom', I returned to my very old RA lists to find that Uwins had exhibited a painting entitled 'Uncle Tom: A Study from the Life' in 1856.    The painting is evidently indeed a study from a live person, rather than a dramatic scene or a fictional character. It must have been painted sometime between 1853 and 1855 when ill-health forced Uwins to retire from his post at the National Gallery and give up oil painting (he died in 1857).  Parts of the picture, such as the table and book are unfinished - although the sketchiness actually enhances the appeal - so it seems likely it was sent to the RA  anyway, to chime with the public mood.  In its first year, a million copies of Stowe's story were sold in Britain and in 1855 it was described as 'the most popular novel of our day.'  
'A Study from the Life' implies that the figure depicted was a man of African ancestry living in London - of whom there were of course many in the 1850s, who could have been employed as a model.  Was he perhaps even closer to the subject? one of the formerly enslaved from the US who sought refuge in Britain during this decade?   Collectively known as 'fugitive slaves' after the law of that name passed in 1850 decreeing that those who had escaped should be returned to their 'owners' (prompting groups to hunt down runaways) several are known to have found asylum in Britain and for some likenesses were published, usually as frontispiece illustrations for their autobiographical 'slave narratives' which served both to create [small] incomes for the authors and contribute to British Abolitionist campaigning. Research continues.  




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