Well, only the Germans called their submarines U-Boats, this was short for the german word unterseeboot which means submarine.
It was Germany.
Germany
Germany, they were submarines.
Germany used U boats.
Germany called there submarines U boats
German submarines were referred to as U-boats during the world wars.
In Germany we say uuuhhh and U is an abbreviation for Unterwasser (underwater) So in English you would say Underwaterboat
Germany made the first submarines in WW1. They were called U-Boats, short for "unterseeboat" Most modern submarines are descended from The Holland, christened in 1897, invented by John Holland.
A German submarine used in WW I was called a U-boat.
A group of German submarines is called a Wolfpak.
The submarines were either called "submarines" or "U-boats." The German submarine was called the "U-boat"
Germany