Gibson was a high school principal in Chester from 1894 until 1898. He served as a Chester Village Trustee from 1895 to 1898. He was a trustee of Norwich University from 1899 to 1909 and again from 1919 to 1935, and served as vice president of the board of trustees. Gibson received an honorary LL.D. from Norwich in 1926. A Republican, after becoming an attorney he practiced in Brattleboro, where he also served as the Windham CountyRegister of Probate and Deputy Clerk of Vermont's United States District Court. From 1904 to 1911 he was a lecturer on constitutional law at Norwich University. In 1906 he was elected to the Vermont House of Representatives. In 1908 he was elected to the Vermont State Senate, and served as President pro tempore. From 1906 to 1910 Gibson served as Brattleboro's Municipal Court Judge. In 1910 he ran unsuccessfully for the Republican nomination for Lieutenant Governor. Gibson became a leader of the Progressive movement in Vermont, which ultimately led to creation of a recognized faction within the Vermont Republican Party, the Aiken-Gibson Wing. The Aiken-Gibson Wing was more liberal than the party establishment, which had been led for years by conservative business interests including the Smith family of St. Albans, the Fairbanks family of St. Johnsbury, and the Proctor family of Proctor. Despite his Progressive views, Gibson remained loyal to the Republicans and worked to keep Vermonters with similar views in the party. To that end, in 1912 he was a delegate to the Republican National Convention. Gibson served as Windham County State's Attorney from 1919 until 1921, and was Secretary of Civil and Military Affairs to Governor James Hartness in 1921.
Military service
From 1899 to 1908 Gibson served in the Vermont National Guard. Enlisting as a private, he was commissioned in 1901. From 1906 to 1908 he served on the staff of Governor Fletcher D. Proctor as a colonel. He served again from 1915 to 1923. Joining the 1st Vermont InfantryRegiment as a captain, he served in the Pancho Villa Expedition in 1915 and 1916. Gibson also served in World War I. As captain and commander of Company I, 1st Vermont Infantry, Gibson served at Camp Bartlett, Camp Greene, and Camp Wadsworth, South Carolina before departing for France in September, 1918. The 57th Pioneer Infantry provided replacement troops for the 83rd Division, with Gibson and a handful of soldiers left to reorganize the regiment and prepare it for a scheduled for deployment to the front lines. The Armistice occurred before the unit moved, and Gibson returned to the United States. At the end of the war he was stationed at Camp Devens, where he received his discharge in March, 1919. Gibson remained in the National Guard, and retired as a colonel upon winning election to Congress.
United States Representative
In November 1923, Gibson was elected to the United States House of Representatives, filling the vacancy caused when Porter H. Dale resigned Vermont's 2nd district seat to become a United States Senator. He was reelected to the Sixty-ninth, and the four succeeding Congresses, serving from November 6, 1923, until his resignation on October 19, 1933. Vermont lost a House district as a result of the 1930 census, and in 1932 Gibson was elected as Vermont's at-large Congressman, defeating Loren R. Pierce in the primary, and going on to win the general election. Governor John E. Weeks had run for the 1st district seat in 1930, and indicated that if elected it would be the capstone of his career and he would not run in 1932, thus avoiding the possibility that two incumbents would run against each other for the at-large seat. During his House tenure, Gibson was chairman of the Committee on Expenditures in the Department of the Treasury and the Committee on Territories.
United States Senate
In November 1933, Gibson was appointed to the United State Senate, filling the vacancy created by the death of Porter H. Dale. He was elected in 1934 to complete Dale's term, and elected to a full term in 1938. Gibson served in the Senate from November 21, 1933, until his death on June 20, 1940. He died in Washington, D.C., and is interred in Morningside Cemetery in Brattleboro.
Family
Gibson married Grace Fullerton Hadley on November 25, 1896. They had four children, Frank Hadley Gibson, Ernest William Gibson Jr., Doris Gibson and Preston Fullerton Gibson. Ernest W. Gibson Jr. succeeded his father temporarily in the Senate and later served as Governor of Vermont and Judge of the United States District Court for the District of Vermont. The younger Ernest Gibson's children included Ernest W. Gibson III, an associate justice of the Vermont Supreme Court. Preston F. Gibson was a lawyer who was active in Republican politics and served as judge of Brattleboro's municipal court.
