What is the origin of the colloquial term “bum” meaning a homeless person?

Question

Just out of curiosity, I was wondering about the history of the term "bum" meaning a homeless person, not the UK version referring to someone's posterior.

Bonus: If you know the background on "Hobo" that would be interesting too, and does it have any relation to the town Hoboken, New Jersey?

Answer 1

Wikipedia offers some speculation on the origin of Hobo. It would seem the etymology revolves around railroads or migrant workers, and that it originated in California.

Author Todd DePastino has suggested that it may come from the term hoe-boy meaning "farmhand," or a greeting such as Ho, boy!. Bill Bryson suggests in Made in America that it could either come from the railroad greeting, "Ho, beau!"

As to the origin of Bum, it seems to come from the German word for loafer (bummler), which comes from loaf (bummeln), presumably from the unemployed trying to obtain bread. Wiktionary

1864, Back-formation from bummer., from German Bummler (“loafer”), from bummeln (“loaf”)

Answer 2

The New Oxford American Dictionary reports that bum is synonym of vagrant ("a person without a settled home, or regular work, who wanders from place to place and lives by begging"), and that to bum means, "to travel, with no particular purpose or destination." On the list of the phrases, it lists also on the bum to mean, "traveling with rough provisions and with no fixed home."

The dictionary reports that the origin of the word is probably from bummer, and that bummer derives perhaps from German Bummler, from bummeln ("stroll, loaf around").

For hobo, the same dictionary reports that its origin is late 19th century, but the word from which it derives is unknown.