Bigger, Faster, Deeper, Comfortable, Deadlier.
Submarines changed war. They played a big part of World War I and II.
Why don't you just Google "World War 1 Submarines?"
World War I submarines were primarily used to locate and attack surface cargo and warships.
Yes
Submarines were sometimes referred to as submersibles.
Yes, German submarines were very effective in both world wars. The Germans built excellent submarines and still do.
2,200,000 Soldiers 97 Warships 40 Submarines.
The US helped France in world war 1 with submarines in the Atlantic.
Steel plates.
326
Atlantic Ocean.
Underseaboats.U-boats