Jonas Mekas, a filmmaker, curator, archivist, critic and all-around evangelist for independently made movies in general, and for those variously known as experimental, underground or avant-garde in particular, died on Wednesday at his home in Brooklyn. He was 96.

His son, Sebastian, confirmed the death.

It is rare to have consensus on the pre-eminence of any person in the arts. But few would argue that Mr. Mekas, who was often called the godfather or the guru of the New American Cinema — his name for the underground film movement of the 1950s and ’60s — was the leading champion of the kind of film that doesn’t show at the multiplex.

A Lithuanian immigrant who, with a younger brother, Adolfas, arrived in New York City in 1949 speaking little English, he became within a handful of years an effective spokesman for avant-garde film. (Adolfas, who died in 2011, became an influential filmmaker, writer and educator in his own right.)

In addition to making his own movies and writing prolifically about the movies of others, Mr. Mekas was the founder or a co-founder of institutions that support and promote independent filmmakers, including, in New York, the influential journal Film Culture, published quarterly from 1955 to 1996; Film-Makers Cooperative, a distribution network; and Anthology Film Archives, the leading library and museum for experimental film. (The critic Andrew Sarris published his influential essay on the auteur theory in Film Culture.)