He served eight terms as a Democrat from 1937 to 1953, having represented the now defunct 8th congressional district, centered about Alexandria.

He was educated in the Winn Parish public schools and received a bachelor's degree from Louisiana State University in Baton Rouge in 1914.

He studied law on his own, was admitted to the bar in 1922, and practiced in Winnfield, where he was city attorney for a time.

While he first ran for Congress, Allen was also a delegate to the Democratic National Convention in 1936, which renominated the Franklin D. Roosevelt and John Nance Garner ticket, an overwhelming winner in Louisiana and nationwide as well.

[citation needed] In 1994, Allen was posthumously inducted into the Louisiana Political Museum and Hall of Fame in Winnfield.