U1, ww1

[Texasuberalles]

I can read the words, can this be from the WW1 sub U1??

[DaveG]

Might be Uhlan or Unteroffizier’s school. My best guess.

Dave

[glaser]

another possibility: Kriegsmarine U-boat number 1 (U-1) which was launched in 1935, although I think that in 1945 they had other priorities instead of engraving bear mugs ...