Actor Robert De Niro has been opening up about his artist father ahead of his HBO documentary, 'Remembering the Artist: Robert De Niro, Sr.' Apart from being the father of a Hollywood icon, De Niro Sr was a talented painter, who also happened to be openly gay. But beyond his sexuality and famous son, there's still plenty to know about the artist, whose work continues to be remembered over 20 years after his death.

Robert de NiroArtistic family: Robert De Niro's father was a painter

Robert De Niro Sr. was born in Syracuse, New York in 1922 to an Italian American father and an Irish American mother. After showing early artistic promise, Robert went to study at the Black Mountain College under the famed artist Josef Albers from 1939 to 1940. He then moved on to study under the expressionist Hans Hofmann, whose tutelage helped him develop and mature as a painter.

While studying under Hoffman, De Niro met another aspiring painter, Virginia Admiral. The couple married in 1942 and a year later their son Robert was born. De Niro was initially part of the abstract artist movement, with his first exhibition taking place at Peggy Guggenheim’s gallery, the home of the emerging Abstract Expressionist movement. Throughout the 1950s De Niro’s work was exhibited in New York and in 1958 he was awarded the Longview Foundation award.

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From 1961-1964 De Niro took his work to France, painting in Paris and the surrounding countryside. During this period a number of his works were purchased by collector Joseph Hirshhorn and are now permanently displayed at the Hirshhorn Museum and Sculpture Garden in Washington, DC. When his son became to achieve fame as an actor in the 70s and 80s, the elder DeNiro’s paintings continued to be exhibited throughout the United States and abroad and he also took work teaching in various art schools and colleges.

Robert De Niro, Sr., died of cancer at age 71, on the morning of May 3, 1993, his 71st birthday. After his death his son dedicated the film A Bronx Tale, his directorial debut, to him. The younger De Niro also kept his father's memory alive by creating The Robert De Niro, Sr. Prize, at the Tribeca Film Institute, to recognize an American artist whose work has made a significant contribution to the field of painting and to support the next generation of artists.

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The future actor and his artist father didn't have a close relationship when Robert was growing up. DeNiro Snr split from Robert's mother when he was young,  after coming to terms with his sexuality. Speaking to Out magazine ahead of the HBO documentary the actor said of his father’s sexuality "I was not aware, much, of it. I wish we had spoken about it much more.” Adding, “My mother didn't want to talk about things in general, and you're not interested when you're a certain age." Describing their relationship DeNiro said they ”had a connection," revealing, "He was absent in some ways. He was very loving. He adored me … as I do my kids."

Robert De NiroRobert De Niro honours his father's memory with an annual prize at the Tribeca Film Institute

Robert De Niro has said he felt it was his responsibility to make a documentary about his father. "I felt I had to. I felt obligated," the actor said. The documentary serves as both a fitting tribute from a son to a father and also a celebration of De Niro Sr.'s work and legacy. "It was the only way to keep his being, his existence alive," De Niro said of the film. "To me, he was always a great artist."

'Remembering the Artist: Robert De Niro, Sr.' premieres on June 9th on HBO.