Walter Flavius McCaleb, historian, novelist, poet, and banker, was born in Denton, Texas, on October 17, 1873, to John Lafayette and Elizabeth (Sweeten) McCaleb. His father was a banker and newspaper publisher in Carrizo Springs. After attending San Antonio Academy, McCaleb enrolled at the University of Texas, where he received a B.A. in literature in 1896 and an M.A. in 1897. He accepted a fellowship to attend the University of Chicago, where he was awarded a Ph.D. in history in 1900. He worked as a freelance writer in New York City from 1901 to 1903; he had begun writing at age nine for his father's newspaper in Carrizo Springs. During his New York years he served as an editor on the staff of the New International Encyclopedia and wrote book reviews for the New York Times, the Nation, and the American Historical Review. His first and perhaps best-known book, The Aaron Burr Conspiracy (1903), was based on research he had done in Mexico in 1898. He maintained a lifelong interest in Burr, and his New Light on Aaron Burr was published in 1963.
McCaleb worked as associate editor of the Philadelphia Public Ledger in 1904. When the Ledger changed owners, he returned to Carrizo Springs to begin his banking career. From that time until his retirement in 1948 he combined the two occupations of banking and writing. He was instrumental in the organization and management of the Cooperative National Bank of Cleveland, the Federation Bank of New York, and the Federal Reserve Bank of Dallas. Among his publications during this time were John H. Reagan's Memoirs, with Specific Reference to Secession and Civil War, which he edited (1906); Ring, A Frontier Dog (1921), a novel for young adults; and Theodore Roosevelt (1931). In 1937 he was special adviser on Puerto Rican affairs to the secretary of state. He maintained his interest in finance and public policy after his retirement from banking. He wrote articles on Mexican banking and the financial aspects of cotton farming in Texas, as well as the book How Much is a $: the Story of Money and Banking (1959). Most of his literary efforts were devoted to history, however; he wrote thirty-six books, including The Spanish Missions of Texas (1956), The Mier Expedition (1959), No Port of Call and Other Poems (1964), and a number of historical works for young readers on such subjects as Stephen F. Austin, William A. A. (Bigfoot) Wallace, the Texan Santa Fe expedition, and the Alamo. McCaleb was a life member of Phi Beta Kappa and an active participant in the Texas State Historical Association. He was instrumental in persuading the University of Texas to preserve the Bexar Archives. He was also a member of the Austin Poetry Society. He and his first wife, Idealie Marie, were married on June 28, 1901; they had four children. After her death he was married again, to Edna Lang, on June 11, 1960. He was a Catholic and a Democrat and lived in Austin from 1948 until his death on March 2, 1967. He is buried in Mount Calvary Cemetery in Austin.