Jeremiah J. O’Keefe, who earned ace status in his first aerial battle when he downed five Japanese planes over Okinawa during World War II and later entered Mississippi politics as a staunch opponent of segregation, died Tuesday at his home in Biloxi, Miss. He was 93.

The cause was congestive heart failure, his son Joseph said.

Mr. O’Keefe, known as Jerry, enlisted in the Navy immediately after the Japanese attack on Pearl Harbor. After earning his wings, and a lieutenant’s commission in the Marine Corps, he joined the VMF-323, a newly formed squadron nicknamed the Death Rattlers.

On April 22, 1945, Mr. O’Keefe and his fellow pilots, assigned to protect American ships unloading troops and supplies in Okinawa, took to the skies.

“We had been patrolling above the picket ships for over two hours without any activity and no enemy planes in sight,” he said on the History Channel program “Dogfights” in 2008. “All of a sudden we were notified by a picket ship below us that a large number of enemy aircraft were coming down from the north — the direction of Japan.”