In 1869 during the Reconstruction era, he and his family left Texas, living for several years in Saltillo, Mexico before their return to San Antonio in 1876.

[1] Hamilton followed his father into politics in the Republic of Texas and the later state, serving in elective office for more than a decade in total.

At age 17, Hamilton Bee was appointed as secretary for the commission that determined the border between the United States and the Republic of Texas.

During the Mexican–American War, Bee served under Benjamin McCulloch's Company A of Col. Jack Hays's 1st Regiment of Texas Mounted Volunteers for a time.

Bee signed up for a second term in 1847—this time as first lieutenant—in Lamar's Company, which was by then a component of Col. Peter Hansborough Bell's regiment of Texas volunteers.

He was repeatedly re-elected and served from 1849 through the end of the Seventh Legislature, for a total of ten years in the House.

Bee was transferred to a field command in 1864 under Lieutenant General Richard Taylor in the Red River Campaign.

Later, despite intense criticism of his handling of his troops, Bee was given command of Thomas Green's division in Major General John A. Wharton's cavalry corps in February 1865.