Henry Gentry was the owner and co-founder of the Gentry Brothers Circus which wintered in Bloomington. He got his start early in the circus business, delivering advertising flyers for one circus at age 16. He worked for that circus for the next seven years, before returning to Bloomington to begin his own dog show with 15 stray dogs he trained himself. The first show opened in 1887 in the Bloomington Opera House. Gentry sold the Gentry Brothers Circus in 1916, and became the manager of the Sells Floto Circus from 1916 to 1920. The Sells Floto circus did not survive the Great Depression. Gentry was also a Bloomington real estate developer.