George E. Chamberlain (January 1, 1854 - July 9, 1928) was an Oregon politician, legislator, and public official. Born near Natchez, Mississippi, he attended private and public schools in Natchez, was clerk in a general merchandise store there from 1870 to 1872. He graduated from the academic and law departments of Washington and Lee University in 1876, where he was a member of Phi Kappa Psi Fraternity. From 1877 to 1879, he was clerk of Linn County, and gained admission to the bar, practicing in Albany, Oregon. He was a member of the Oregon House of Representatives from 1880 to 1882, and was district attorney for the third judicial district from 1884 to 1886. He was appointed attorney general of Oregon, holding that office from 1891 to 1894.
In 1902, Chamberlain was elected Governor of Oregon, was reelected in 1906. In 1908 he was elected as a Democrat to the U.S. Senate; he was reelected in 1914 and served from March 4, 1909, to March 3, 1921. He was an unsuccessful candidate for reelection to the Senate in 1920; while a Senator, he was chairman of the Committee on Geological Survey (Sixty-second Congress) and a member of the Committee on Military Affairs (Sixty-third through Sixty-fifth Congresses), the Committee on Public Lands (Sixty-third Congress), and the Committee on Expenditures in the War Department (Sixty-sixth Congress). The Chamberlain Military Preparedness Bill of 1918, which he wrote, bears his name.
He was a member of the United States Shipping Board from 1921 to 1923 and engaged in the practice of law in Washington, D.C.; he died there in 1928, and interment was in Arlington National Cemetery.
John Archer and Stevenson Archer, both United States Representatives from Maryland, were Chamberlain's grandfather and great-grandfather, respectively.