In 1515 in northern Italy.
After 1798 Napoleon forced Switzerland to support his attempt to conquer Russia with troops - and the country was forced to form a "pillow" between the big nations of Europe after 1815 which includes to become neutral.
Last small clashes were in World War 2 with German luftwaffe (and allied bombers).
WW2
A war in Kashmir between India and Pakistan was fought in 1965.
1846 to 1848
War of 1812 (June 1812 - February 1815)
I think it was at Gettysburg, PA
Switzerland has not fought in a war since 1815.
Switzerland
The most recent war fought in Switzerland is the Napoleonic wars. Since then (since 1815) Switzerland has been neutral.
switzerland
Switzerland
The last battle of the American Civil war was fought in Texas, at Palmito Ranch on May 12-13, 1865.
ca
The Falklands War of 1982
poland,italy,belgium,switzerland
Iraq.
WW2
Finland,Spain and Switzerland were locked in a 3 way fight for 4 out of the 7 years ww1 was fought.