William Maxwell Howell was born on December 22, 1915, in Lonoke, Arkansas. He was the son of Flavius Joseph and Marguerite Howell. Max graduated from Little Rock High School (now Central High School). After graduation, he married Lula Agnes Gray, with whom he had two children. They later divorced, and in 1967, he married Mildred Inez Donham, who had four children from a previous marriage. He entered Arkansas Law School and passed the bar in 1940.
Shortly after becoming a lawyer, he was hired by the Farm Security Administration in January 1940. At the outbreak of World War II, he enlisted in the Army Air Corps on July 20, 1942, in Little Rock. He served for the duration of the war and joined the Arkansas Air National Guard once his enlistment was finished in 1948. He transferred to the Army National Guard in 1950. He spent his entire thirty-year career in the National Guard in the Selective Service Section, becoming Chief in 1972. Upon his retirement in 1975, he had attained the honorary rank of brigadier general.
Howell joined the Talley and Owen law firm in 1946. In 1954, Howell and Dale Price left the firm to open their own practice.