Walker, a graduate of Gonzaga University, (Spokane, Washington) in 1906 and Notre Dame Law in 1909, practiced law in Montana and acted as the local Democratic chairman in the 1920 presidential election campaign. He moved to New York City in 1925 as vice-president and general counsel of a movie theatre chain, while also practicing independent corporation law.

He supported Franklin D. Roosevelt's campaigns for governor in 1928 and the presidency in 1932. During the 1932 campaign he served as Treasurer of the Democratic National Committee. President Roosevelt appointed him executive secretary of his President's Executive Council in 1933, and he subsequently acted as executive director of the National Emergency Council.

In 1940 he was appointed to succeed Jim Farley as Postmaster General of the United States, in which position he served until 1945. In 1946 he was appointed by President Truman as alternate delegate to the first United Nations General Assembly session in London. He returned to his business interests in N.Y. as director of W. R. Grace & Co. and the Grace National Bank of New York.

Frank C. Walker was born on 30 May 1886 to Ellen and David Walker in Plymouth, Pennsylvania. He was the eleventh of fourteen children. Ellen Walker ran a general store in Plymouth during Frank's earliest years while her husband tried prospecting in Montana. By 1890, the family had enough money to settle together in the growing mining town of Butte, Montana, where Frank spent most of his youth.

The Walkers initially prospered in Montana. As the owner of small mines or as the superintendent of large mines, David Walker was able to provide for his family until falling ill in 1901. At age fifteen, Frank Walker dropped out of school and worked for two years as a tool carrier in the mines to help support the family.

Family finances improved and Frank was able to continue his education. He spent three years in preparatory and collegiate courses at Gonzaga University in Spokane, Washington. After graduating from Gonzaga in 1906, he enrolled in the University of Notre Dame Law School and began an affiliation with that university which lasted throughout his life. Walker graduated from Notre Dame in 1909 and returned to Butte to commence his legal career. He first served as Assistant County Attorney until 1912 when he was elected to the Montana state legislature. Walker served only one term in the legislature before leaving to establish a law partnership with his brother, Thomas.

In 1914, Walker's attention was turned from his career to other concerns. In November he married Hallie Boucher, daughter of a Butte merchant. The year of Walker's marriage was also the start of World War I, and he served as a first lieutenant, arriving in France just one week before the armistice. After the war, the Walkers saw the birth of a son, Thomas, born in 1921, and a daughter, Laura, born in 1924.

Following the birth of his daughter, Walker left his law partnership and Butte to join his uncle, M.E. Comerford, in the successful Comerford Amusement Enterprises in New York City. Walker began as general counsel to the chain of Comerford theaters; by 1935 he was the chief operating officer. Walker's move to New York was important not only for his legal career but also for his future in politics. Exposure to political corruption and the struggles of labor in Butte's mining industry had provided him with firsthand knowledge of the need for progressive reforms. Now association with the progressive governor of New York, Franklin D. Roosevelt, confirmed Walker in those political beliefs.

Walker first met Roosevelt in 1920 when FDR was running for vice-president and was on a campaign trip that took him to Butte. But Walker's friendship and political alliance with the future president really began during Roosevelt's gubernatorial reelection campaign in 1930. By 1932 Walker was part of the inner circle of Roosevelt's emerging campaign for the presidency. A member of FDR's pre-convention committee, Walker was one of the principal donors to the early campaign. After FDR's close convention victory in Chicago, Walker was named Democratic National Committee (DNC) treasurer in August 1932.

With Roosevelt's election to the presidency in November 1932, Walker played an important role in the organization of the new administration. He advised Roosevelt on cabinet appointments as well as lower level positions. Initially uninterested in a post for himself, by the summer of 1933 Walker had been persuaded to head the Executive Council, a new body established that July to coordinate the administration's activities with appropriate governmental agencies. Comprised of cabinet members and agency heads, the Executive Council met weekly with the president.

Walker's role as coordinator of federal departments and agencies was expanded again when in November he was named director of the National Emergency Council (NEC). The NEC functioned much like the Executive Council, but it had fewer members, was national in scope, and concerned itself only with New Deal programs. Walker ran both councils from the same office. By October 1934, the two councils merged into one, keeping the name NEC.

Much of Walker's work with the NEC was with subsidiary governmental units. At his direction a government manual was prepared outlining all government departments and agencies. The United States Information Service was formed to disseminate information to the general public about the function and personnel of all government departments and agencies. Walker also helped plan and achieve passage of the National Housing Act, an attempt to encourage renovation of existing housing stock as well as the creation of new housing.

After the National Housing Act was signed in June 1934, Walker took a leave of absence from the government to concentrate on family business. He had never actually given up his work with Comerford Enterprises, commuting between New York and Washington several days each week. But Walker's plan to work only in one city was temporarily postponed when the following April he acceded to a request from Roosevelt to head the NEC's Division of Applications and Information (DAI), an office designed to review, rout, and report to the press on all applications to the four billion dollar Works Relief Program.

Walker spent an additional eight months dividing his time between the government and his private interests, but when the illness of his uncle, M.E. Comerford, and the death of his cousin, M.B. Comerford, gave him control of Comerford Enterprises, he needed to devote more of his time to business affairs. With his final resignation from the NEC, Walker concentrated his efforts on promotional activities for his theaters, in particular a quiz contest for moviegoers called "Motion Pictures' Greatest Year."

The circumstances of the 1940 presidential election conspired to draw Walker back into public life. James A. Farley, estranged from Roosevelt over the issue of a third term, resigned as Postmaster General in August. Roosevelt turned to Walker to fill the vacancy and Walker moved his family to Washington.

While serving as Postmaster General Walker also acted as a negotiator and advocate for Roosevelt's international policies. In his apartment in Washington, Walker and Secretary of State Cordell Hull held delicate informal negotiations with representatives of the Japanese government. But with the bombing of Pearl Harbor the focus of Walker's work in Washington turned back to the post office. The need was urgent to get mail to the millions of Americans stationed on two fronts overseas, and Walker is credited with effecting a remarkable transformation in the efficiency of the agency's operation to handle that task. In January of 1943, Walker added to his duties by succeeding Edward Flynn as chairman of the Democratic National Committee. Walker held that position for slightly less than a year, but during that time established a framework for FDR's successful fourth term presidential bid.

Walker's involvement in national politics virtually ended with the death of Roosevelt in 1945. Public service had been a personal favor to Roosevelt; Walker resigned as postmaster general in June of 1945. He did agree to one last act of public service early in 1946: he accompanied Secretary of State James Byrnes, Eleanor Roosevelt, and Edward R. Stettinius, Jr., as a member of the United States delegation to the first session of the United Nations Organization (UNO) in London.

Returning to New York, Walker resumed his work with the Comerford theaters. He also involved himself with W.R. Grace's shipping and banking interests, serving as a director of W.R. Grace and Company and the Grace National Bank.

Throughout his life Walker devoted a considerable amount of time to charitable activities. He worked as treasurer of Catholic Charities for the Archdiocese of New York, and as a member of the boards of the Franklin D. Roosevelt and Harry S. Truman presidential libraries, as well as the Board of Lay Trustees of the University of Notre Dame.

In 1952, Walker retired and started work on his memoirs with the help of his aide, Paul Kirby Hennessy. The work was never completed.

Frank C. Walker died on 13 September 1959.