A native of Queens, New York, Kohler was a lifetime queer activist in New York City, who also fought for the rights of many other people and animals. He was at the Stonewall riots, and considered a father figure to many of the young transport people, such as Sylvia Rivera and Marsha P. Johnson, as well as to younger generations of activists. Kohler served in the United States Navy in the South Pacific Theater during World World War II, was the manager of the New York gay bathhouse, Club Baths, was among the first agents to represent non-famous Black artists, owner of the popular gay store The Loft on Christopher Street, and a lifelong activist.
He died of lung cancer on December 5, 2007, at the age of 81, in the Charles Street (West Village) apartment that he had lived in for 45 years.
Though Kohler is best known for his role at the Stonewall riots and his early involvement with the Gay Liberation Front, he was active with many movements and groups, including the Congress of Racial Equality (Congress of Racial Equality), the Black Panther Party, Acting Up, Sex Panic, the Neutral Zone, the New York City Acquired Immune Deficiency Syndrome Housing Network (NYCAHN), Irish Queers, Federation Up Queers, animal rights groups, and FIERCE!.