The first Enterprise in US navel service was a sloop captured from the British in 1775.
The most famous USS Enterprise,CV 6 was commissioned May 12, 1938. In WWII she participated in almost every major battle. Her first action of the war came on the first day of US involvement, after the Japanese attacked Pearl Harbor. She was deployed to the Battle of Midway where her aircraft participated in the sinking of three Japanese carriers, ending the Japanese offensive in the Pacific. 

The most recent USS Enterprise (CVN 65), is the longest serving ship of the name. Commissioned November 25 1961 as the first nuclear powered aircraft carrier built.