Son of a Norwegian father and a Swedish mother, Öyvind Fahlström was born and raised in Brazil. At the age of 10 he was sent to Sweden to spend the summer with his grandfather and aunt. A month after his arrival, Germany invaded Poland, marking the beginning of the Second World War. When his parents were able to return to Stockholm nine years later, he was already an adult. In 1949, forced to choose between military service in Sweden or Brazil, he adopted Swedish citizenship and renounced his Brazilian passport. After studying the classics and art history at Stockholm University, he travelled to Italy and Paris where he was in contact with circles of poets and painters. It was through poetry and musical composition that he entered the world of visual art, which he always understood as being part of the same creative field. In 1952, he presented his first installation, Opera, a drawing in marker pen and ink on paper, and in 1954 published his manifesto Hipy Papy Bthuthdth Thuthda Bthuthdy: Manifesto for Concrete Poetry, an experimental text that tries to free literature from its tradition. In 1961 he moved to New York, spending his summers in Sweden, France and Italy.

Fahlström's work displays a complexity that distances it from Pop art. While the use of images from mass culture and comics is consistent with this movement, an interest in rules as an organising principle sets him apart as a unique sui generis artist. His work is articulated by the experiments of Concretism, a movement wherein words are freed from their ordinary meaning. The gap between the reality of colonial life and Europe's welfare society, which he knew first hand, made him more sensitive to the differences between the two worlds and the abuses of the poor by the rich. For this reason, he incorporates diverse references to the politics and culture of his time. Author of multiple works including poetry, concrete sound compositions, collages, drawings, installations, films, performances, paintings, and critical and literary texts, Fahlström conjoins politics and sexuality, humour and criticism, writing and image. His 'variables', his labyrinthine drawings, the use of words and multiple references to capitalism are an important part of his creative language.

Fahlström's works have been exhibited in major art centres, including the Moderna Museet in Stockholm (1979), the Georges Pompidou Centre in Paris (1980), the SR Guggenheim Museum in New York (1982), the Walker Art Center in Minneapolis, Minnesota (1983), IVAM in Valencia (1992) and MACBA in Barcelona (2000–1). Since 1999, the Öyvind Fahlström Foundation and Archives have been based at MACBA.