General Discussion
In reply to the discussion: Shakespeare and Myths About Genius [View all]muriel_volestrangler
(105,457 posts)who was "the other town drunkard" with Tom Blankenship.
https://web.english.upenn.edu/~cavitch/pdf-library/Lamb_Roots.pdf
From an academic article (you need a free sign-in to read it): https://www.jstor.org/stable/461003
"Finn, a common enough name then and now, is also joyously and unmistakably Celtic and, as such, had connotations of the Irish in nineteenth century America: typically servants and laborers in a status only slightly higher than that of the Negro ... The Irishness of Huck was not lost on E. W. Kemble, the illustrator of the first edition, who emphasized that aspect of the boy's appearance more than Twain thought necessary (footnote of Twain letter to his publisher: "the boy's mouth is a trifle more Irishy than necessary" )."
Or another analysis contrasting Finn's Irishness with the vast majority of surnames in the novel being Anglo-Saxon: https://www.jstor.org/stable/27746723
Also remember that log cabins would not be seen as "Finnish"; Scandinavian, perhaps, but Finland was a border region that Sweden and Russia had fought over, and the latter had won, by the start of the nineteenth century.
Twain himself said the name was to imply "of lower extraction" than Sawyer, if you want the stereotype to hunt:
https://twain.lib.virginia.edu/onstage/mttalks.html