^ One is from English, the other from German??? So I looked it up. From the Oxford English Dictionary. The number are from the year the word was first used, er can be proven to have been used.
bum, n.1
1387 J. Trevisa tr. R. Higden Polychron. (St. John's Cambr.) (1876) VI. 357 It semeþ þat his bom is oute þat haþ þat euel [ficus, i.e. piles].
a1547 J. Redford Moral Play Wit & Sci. (1848) 20, I woold thy mother had kyst thy bum!
1550 R. Crowley One & Thyrtye Epigr. sig. Dviii, A bumbe lyke a barrell wyth whoopes at the skyrte.
1600 Shakespeare Midsummer Night's Dream ii. i. 53 Sometime, for three foote stoole, mistaketh mee: Then slippe I from her bumme, down topples she.
1638 A. Read Treat. 1st Pt. Chirurg. xii. 97 To pull the feathers from the bummes of hens or cocks.
1708 London Gaz. No. 4441/4, A Sorrel Gelding, with‥some white Hairs on his Bumb.
?a1786 R. Burns Poems & Songs (1968) I. 197 Many a tatter'd rag hanging over my bum.
1816 W. Kirby & W. Spence Introd. Entomol. (1828) II. xxiii. 329 Heating their bums or tails against them as they creep along.
bum, n.4
1864 Gold Hill (Nevada) News 15 Apr. 5/1 The policemen say that even their old, regular and reliable ‘bums’ appear to have reformed.
1891 C. Roberts Adrift in Amer. 68, I don't believe in feeding professional bums.
1926 J. Black You can't Win ix. 104 A thoroughgoing bum from the road. The term ‘bum’ is not used here in any cheap or disparaging sense. In those days it meant any kind of a traveling thief.
1931 E. Linklater Juan in Amer. ii. iii. 75 I'll fix the dirty bum that framed me!
1933 Observer 2 Apr., ‘Bum’, a term of affectionate obloquy which young American friends have applied to me‥means not merely a fool, but a droning fool.
1941 A. L. Rowse Poems of Decade 103 Lord, how he pontificates, Lays down the law to these poor bums.
1958 Punch 5 Feb. 218/2 The bums in the dosshouse have reached bottom.
< I am not feeling much better now.
V Are you feeling much better now? "Buddy Ryan: ...but I'm feeling MUCH better now!" Night Court 1984 Everyone who has seen this episode, remembers this line.