Trench warfare was one of the new forms of warfare introduced during World War 1. Another new form of warfare was chemical warfare.
World War 1 introduced aerial warfare with airplanes and trench warfare
Ypres, Belgium
chemical warfare was prevalent , later outlawed by the Geneva convention
Machine GunsTanks
The British tank, and the trenches.
Trench Warfare.
Trench Warfare
Naval warfare in the Mediterranean during World War I happened in 1919-08.
The machine gun changed warfare
trench warfare
Mustard Gas was introduced into warfare in September of 1917.
Yes, Income tax was introduced to Canada during World War 1. It was introduced to help pay for the costs of everything needed for the war.