Siira is a rare Finnish surname found mostly in Koillismaa, Kainuu and Karelia. The name Siira can be found in other countries such as Russia, Norway, Sweden and the United States.
In the Finnish civil war in 1918, five Siiras died in Finland. Of those who died, 3 belonged to red and 2 to white. In the wars in Finland in 1939–1945, 24 Siiras were killed. The number covers those who served in the armed forces, but not civilian victims of war.