Donald Henry Rumsfeld (born July 9, 1932) is a United States businessman, politician, the 13th Secretary of Defense under President Gerald Ford from 1975 to 1977, and the 21st Secretary of Defense under President George W. Bush from 2001 to 2006. He is both the youngest (43 years old) and the oldest (74 years old) person to have held the position, as well as the only person to have held the position for two non-consecutive terms, and the second longest serving, behind Robert McNamara. Rumsfeld was White House Chief of Staff during part of the Ford Administration, and also served in various positions in the Nixon Administration. He served four terms in the United States House of Representatives, and served as United States Ambassador to NATO. He was an aviator in the United States Navy between 1954 and 1957 before transferring to the Reserve. In public life, he has served as an official in numerous federal commissions and councils.

Donald Rumsfeld was born on July 9, 1932, in Evanston, Illinois, to George Donald Rumsfeld (Illinois, October 10, 1904 – September 1974) and Jeannette Huster (Illinois, May 27, 1903 – May 3, 1988). His great-grandfather, Johann Heinrich Rumsfeld, emigrated from Weyhe near Bremen in Northern Germany in 1876. Growing up in Winnetka, Illinois, Rumsfeld became an Eagle Scout in 1949 and is the recipient of both the Distinguished Eagle Scout Award from the Boy Scouts of America and its Silver Buffalo Award in 2006. He was a camp counselor at the Northeast Illinois Council's Camp Ma-Ka-Ja-Wan in the late 1940s and a ranger at Philmont Scout Ranch in 1949. Rumsfeld bought a vacation house 30 miles (48 km) west of Philmont at Taos, New Mexico.

Rumsfeld went to Baker Demonstration School, a private middle school, and attended and graduated from New Trier High School. He attended Princeton University on academic and NROTC partial scholarships (A.B., 1954). In extracurricular activities he was an accomplished amateur wrestler and a member of the Lightweight Football team playing defensive back, and at Princeton he became Captain of both the varsity wrestling team and the Lightweight Football team. While at Princeton he roomed with another future Secretary of Defense: Frank Carlucci.