Ski warfare

Muscovite campaign against the Lithuanians, a painting by Sergei Ivanov (1903).
A Norwegian soldier on skis 1801.
Imperial Japanese Army ski troops on maneuveurs in Chishima Islands, circa 1940
Finnish ski troops in Northern Finland during the Winter War in January 1940.
German Gebirgsjäger with skis in 1942.

Ski warfare is the use of ski-equipped troops in war.