Green’s Dictionary of Slang

boho n.1

also bohoe
[abbr. SE Bohemian, a Czechoslovak]

(US) a Czech immigrant.

[US]T. Čapek Čechs in America 114: In some localities Bohemians are called ‘Bohoes’, in others ‘Bohunks’; less familiar are the terms ‘Cheskey’ and ‘Bootchkey’ .
[US]Mencken Amer. Lang. (4th edn) 295: For Czech: bohoe, bohick, bohee, bohunk, bootchkey and cheskey.
[US]Chapman NDAS 36/2: boho n. [...] An immigrant from central or eastern Europe, usu a Czech, Slovak.