Caspar Willard Weinberger was born in San Francisco, California, on August 18, 1917. He received his A.B. magna cum laude (1938) and LL.B. (1941) from Harvard University.

Weinberger practiced law in California as a partner of Heller, Ehrman, White and McAuliffe from 1947 to 1969. He was also involved in electoral politics, serving in the California legislature for the Twenty-first District from 1952 to 1958. Weinberger was California director of finance under Governor Ronald Reagan (1968-1969), and then he went to Washington to become chairman of the Federal Trade Commission (1970). 

Weinberger worked in the administration of Richard Nixon as deputy director of the Office of Management and Budget (1970-1972), director of the Office of Management and Budget (1972-1973), and counselor to the President (1973). He also served Presidents Nixon and Gerald Ford as secretary of Health, Education, and Welfare from 1973 to 1975. At HEW, Weinberger, who had earned the sobriquet "Cap the Knife," attempted to cut spending in the department and transfer the costs of entitlement programs to the states.

Following his tenure with the Ford administration, Weinberger returned to California as special counsel, vice president, and later director of Bechtel Corporation.

In 1981, President Ronald Reagan appointed him secretary of Defense, and Weinberger remained in that post until 1987. After leaving government service, Weinberger became publisher and chairman of ForbesForbes magazine. In 1990, he wrote Fighting for Peace, followed by The Next War in 1996. He died in 2006.

Allyson Hoffman contributed to the writing of this entry.