Yes. Actually, the first submarines were used a number of years before 1912.
Germany must surrender its submarines and weapons
2,200,000 Soldiers 97 Warships 40 Submarines.
It was Germany.
Germany
Germany called there submarines U boats
Germany made its own submarines and had been doing that since the days of WW 1, long before Hitler.
U-boats aka submarines
sink allied supply ships to England
Britain, France, Germany, Italy and USA all used submarines during WW1
use of submarines
Nobile menzogna - 1912 was released on: Italy: 1912 USA: October 1912 Germany: 1913
1914-1918.