Born in Detroit in 1932, Byars studied psychology and aesthetics. Between 1958 and 1967 he made frequent trips to Japan, during which he considered the relationship between Western rationalism and Eastern mysticism. Byars then took up a nomadic existence and in the 1970s began to perform more, in public spaces and institutions in European and the United States.
His first solo show was held in the emergency exit stairwell of MoMA in New York, in 1958. This was followed by shows at the Willard Gallery in 1961, in Japan from 1962, at the Metropolitan Museum of Art in 1970, then at MoMA in 1976.
He gave performances at the Museum of Fine Arts in Bern, which was the starting point for other shows across Europe, in Amsterdam, Berlin, Geneva, London, Paris, Cologne, Venice, Brussels and Marseille.