Simon Bolivar Buckner Jr. was a lieutenant general in the United States Army during World War II who served in the Pacific Theater. As commanding general of Alaska Defense Command, Buckner commanded American-Canadian forces in the Aleutian Islands campaign, including the Battle of Attu and the Kiska Expedition. Following that assignment, he was promoted to command the Tenth Army, which conducted the amphibious invasion of the Japanese island of Okinawa in 1945. He was killed during the closing days of the Battle of Okinawa by enemy artillery fire, making him one of the highest-ranking United States military officers lost to enemy fire during World War II.

In the United States Armed Forces, a lieutenant general is a three-star general officer in the United States Army, Marine Corps, Air Force, and Space Force.