Kamikaze means Divine Wind in Japanese.

The term was first used in 1281 to describe an event in 1274 when China and Mongolia attempted to invade Japan. The situation for the Japanese was hopeless, but a storm broke up the invading fleet and Japan was saved. The Japanese called this storm the Divine Wind.

During World War II, in 1944 Japanese forces were at a disadvantage against the Americans in the Pacific.
So they formed special suicide forces that were operators of aircrafts, guided bombs and small boats. It all started when Rear Admiral Arima attacked an American aircraft carrier with an aircraft causing serious damage.

[Source: el.wikipedia.org]