WASHINGTON (AP) — Martin Sullivan, the former director of the Smithsonian’s National Portrait Gallery, has died at his home in Piney Point, Md. He was 70.

Museum officials said Sullivan died Tuesday after a series of illnesses. He joined the National Portrait Gallery in 2008 and left in May 2012, citing health reasons.

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At the Portrait Gallery, Sullivan is credited with reinvigorating its focus on portraiture as a medium of visual biography. During his tenure, the museum expanded its commissions of new works of notable figures, beyond presidents and first ladies.

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Sullivan had a long career leading U.S. museums. He previously served as CEO of the Historic St. Mary’s City Commission in Maryland and was director of the Heard Museum in Phoenix and director of the New York State Museum in Albany, N.Y.

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