Robert April was a prominent 23rd century Starfleet officer who was, perhaps most famous for his stint as the first captain of the USS Enterprise. During the 2240s, April oversaw the construction of components for a Constitution-class starship at the San Francisco Naval Yards. That vessel eventually became the USS Enterprise which April later commanded from 2245 to 2250; his wife Sarah served as the first chief medical officer aboard the USS Enterprise. 

Fun fact: Commodore Robert April was played by James Doohan and Dr. Sarah April was played by Nichelle Nichols.