Early in his career, George Ruby worked in Haiti as a correspondent and helped African Americans seeking freedom from slavery and racial strife. Later, after being beaten by a white mob while trying to establish a Common School in Jackboro, Louisiana, Ruby moved to Galveston County in 1866. He joined the Freedmen's Bureau and administered its schools.
By 1868, Ruby was closely associated with the Union League. This enabled him to rise within the ranks of the Republican Party and influence the large African-American constituency of the party. He was a delegate to the National Republican Convention, the only African American from Texas. He also was one of ten African Americans elected delegates to Texas's Constitutional Convention of 1868-69.
As a Senator in the 12th Legislature, Ruby was appointed to the Judiciary, Militia, Education, and State Affairs committees, which performed 75 percent of the work of the Senate that session. Ruby introduced successful bills to incorporate Texas railroads and a number of insurance companies and to provide for the geological and agricultural survey of the state. According to one scholar, "Senator Ruby became one of the most influential men of the 12th and 13th Legislatures." Another account stated that he was the "most prominent black politician of Reconstruction." Ruby established Galveston's first Labor Union of Colored Men. Before the Civil War, whites dominated work on the docks, but after 1870, African Americans received a fair share of the work, thanks to Ruby's efforts.