WWII: annual production of artillery guns 1939-1945, by country

The use of artillery guns, including cannons and Howitzers, became more important than ever during the Second World War. The increased role of tanks, armored vehicles, and planes meant that defending forces would require advanced technology to withstand enemy attacks, with anti-vehicle and anti-aircraft guns coming to the fore. As the war progressed, guns grew larger in caliber in order to deal with improvements in tank armor, with such developments most obvious between the German and Soviet forces where the supporting role of tanks and guns played the largest role in the conflict. In the early stages of the war, the German 8.8cm Flak anti-aircraft gun proved so successful and versatile that it was also used as anti-tank artillery, before it became the standard gun mounted on the Tiger tank series.

Guns and cannons were also mounted to warships or aircraft, accompanying weapons such as machine guns and torpedo launchers - around half of all guns produced by the United States were used in a naval or aerial capacity.