Reuben had moved to New Orleans in 1852, arriving as a train engineer. He studied law, served briefly in the Confederacy during the War Between the States, and was married twice.
Reuben practiced law in Baton Rouge and New Orleans, retiring to Crowley, LA, before 1900. He also was a judge and a prosecutor. He was known as a tough taskmaster to his five sons. He sent them each to work early in their lives. Hubert sold products on trains when he was 12 years old. The boys were tossed in the river to sink or swim. One grandson remembered how his father told of being kicked off a streetcar by his father because he didn't have the fare. A strapping man in otherwise good health, Reuben suffered from appendicitis, but physicians refused to remove his appendix because of his age (76). Thus he died on Dec. 14, 1903 in Dallas, Texas, where he was living with his son, Percy R. Knickerbocker, pastor of the Methodist church there. Reuben was raised as an Episcopalian and switched to Methodism when he married Emma. It was their compromise for she had been a Presbyterian. Reuben is buried in Oakland Cemetery in Dallas where his sons, Percy and Hubert, and daughter-in-law, Julia, also are laid to rest.