Throughout both World War I and World War II cats in war exhibited bravery in extreme situations. Serving on battleships and in the trenches, cats proved their heroism in dire circumstances by doing what they were best at, being mousers, mascots, and affectionate companions. During WWI, the British employed more than 500,000 cats to clear the often treacherous trenches of mice and rats. Cats also alerted troops to drifting poisonous gas clouds saving thousands of lives. Both cats and dogs were even accused of spying for the Germans. When they were observed crossing back and forth across British trenches by the 36th brigade of the 12th Division in July 1915, officers believed that they might have been delivering German messages across the lines.
During WWII, cats protected valuable food stores from vermin and were considered so important that they each received an extra powdered milk ration for their service. The United States even sent thousands of American cats to France in its ‘Cats for Europe’ campaign.
Most pictures of cats during WWII show them as affectionate companions or mascots. Images of Felix the Cat, already so important to American history, were used as battalion and regimental emblems in WWI and WWII, and fighter pilots often drew pictures of cats on the sides of their planes. Felix type emblems were also worn as company insignia.