James Blackwood Pearson was born May 7, 1920 in Nashville, Tennessee. His father, a Methodist minister, later relocated his family to Virginia.

It was during World War II that Pearson had his first close look at Kansas. As a navy pilot he served at the Olathe Naval Air Station, flying planes for the Naval Air Transport Service from 1943 to 1946. He left the service with the rank of Lieutenant. Pearson had attended Duke University and returned to the East to earn his law degree from the University of Virginia School of Law. He moved back to Johnson County, Kansas in 1950 and opened a law office in Mission.

Within a short period of time, Blackwood was serving as city attorney for both Westwood and Fairway, and in 1952 became the assistant county attorney. Becoming involved in local Republican Party politics, Pearson was elected probate judge in 1954 and state senator in 1956. After a four-year term in the Kansas Senate, he became State Chairman for the Republican Party.

Governor John Anderson, recognizing Pearson's solid political experience, appointed him on January 31, 1962, to the U.S. Senate to fill the vacancy created by the death of Senator Andrew F. Schoeppel. That November Pearson was elected to serve the remaining four years of Schoeppel's term. In 1966 and 1972 Pearson was re-elected to six-year terms.

During his 17 years in the United State Senate, Pearson served on numerous committees, subcommittees, and commissions. His main committee responsibilities during this time involved the Public Works, Interior, Commerce, Armed Services, and Foreign Relations Committees. He also took part in many international conferences and fact-finding missions. His committee seats and increasing seniority through the years gave Pearson considerable political clout. His independent voting record reinforced this fact by giving him a wide base of respect from both Republicans and Democrats in the Senate. Comfortable in the moderate and conservative camps, Pearson nevertheless was not shy in voting with liberal Democrats on issues that were to him a matter of conscience.

In 1978 Pearson surprised many people by choosing not to run again for another six years in the Senate. Upon his retirement, Nancy Landon Kassebaum was elected to his seat.

After his years in the Senate, Pearson was associated with the Washington office of the law firm LaBeouf, Lamb, Lieby and MacRae, in addition to serving on various boards and commissions. He died January 13, 2009, at his home in Gloucester, Massachusetts, and was survived by his second wife, Margaret Pearson, and children James, Thomas, William, and Laura from his first marriage to Martha (Mitchell) Pearson.