Ulysses Erwin Sibely was born April 9, 1890 in Baldwin County, Georgia. He is the son of James Longstreet Sibley and Mattie Erwin Sibley. His father, who was a farmer by occupation, was born in Baldwin County, and his mother was also a native Georgian who died in 1930. The Sibleys are still a prominent family in Middle Georgia.
Erwin Sibley attended Georgia Military College, where he was a member of the class of 1906. He graduated with Bachelor of Laws in 1910 from the University of Georgia. Admitted to the Bar of Georgia in the same year, he began practicing law in Milledgeville. In 1911, he formed a partnership with his brother, John A. Sibley, under the firm name of Sibley and Sibley. In 1913, he became secretary to the Hon. J.R. Pottle, Judge of the Georgia Court of Appeals in Atlanta, Georgia. In 1914, Sibley became secretary to Chief Justice Fish of the Supreme Court of Georgia, and in 1920, he admitted his own younger brother, Marion Sibley, as a partner and associate in the practice of law. For a decade, Sibley practiced law independently, but in 1930, he and Marion H. Allen created a partnership, forming the firm of Sibley and Allen. This firm influenced life in Milledgeville, and Sibley became recognized as a foremost member of his profession. Sibley and Allen continued until Allen's appointment to the Office of the United States Collector of Internal Revenue, when he moved to Atlanta, Georgia.
Sibley also interested himself in community affairs as a corporation director and as council to the First National Bank of Milledgeville. He was at one time County Solicitor of Baldwin County and special attorney of the Department of Justice under the direction of the United States Attorney General. Sibley did considerable work as a Four Minute Speaker during World War I while stationed at Camp Gordon in Augusta. He entered the United States Navy as a Lt. Commander during World War II and received his honorary discharge as Commander on Februrary 12, 1946.
He returned to practice law after his discharge from the Navy and to his position with United States Department of Justice. He completed his work for the Department of Justice on August 29, 1947. At that time he received the commendation of the United States Attorney General: "Since May 5, 1934, you have performed excellent service for the Lands Division. Your enterprise and fine spirit of cooperation have been greatly appreciated."
Sibley belonged to the Free and Accepted Masons, and he was a past president and district Lieutenant-Governor of the Kiwanis Club, a former Boy Scout Master, and member of the Board of Trustees of the Presbyterian Church. Sibley also maintained a close friendship with Congressman Carl Vinson, which provided him access to Washington and Atlanta political circles. In 1932, he was a delegate to the National Democratic Convention working at the headquarters of Franklin D. Roosevelt.
During the time he practiced law, his clients included Merhcants and Farmers Bank of Milledgeville, Division Council for the Central of Georgia Railway Company, Georgia Railroad and Banking Company, Georgia Power Company, Milledgeville Coca-Cola Company, Hardware Mutual Company, United States Fidelity and Guaranty Company, Allen's Hospital Inc., Oconee Clay Products Company, Milledgeville Tractor and Implement Company and Milledgeville Mills (N.T. Stevens and Sons Company).
He was a member of the American Legion and past president of the Baldwin County Progressive Farmers Club. Sibley served as vice president of the Milledgeville Bar Association, as well as the vice president of the Georgia State Bar Association and chairman of the Executive Committee of the American Bar Association. Sibley also served as a Baldwin County Superior Court Judge until his death in 1979.