Manuel Luján Jr., a former 10-term Republican congressman from New Mexico and a secretary of the interior whose efforts to balance development and conservation of federal lands often left him at loggerheads with environmentalists, died on Thursday night at his home in Albuquerque. He was 90.

A granddaughter, Amy Everett, confirmed the death. In a statement, Gov. Michelle Lujan Grisham of New Mexico, a Democrat and a distant cousin of his, called Mr. Luján “the picture of a statesman.”

The scion of a well-connected New Mexico family, Mr. Luján mounted his first congressional campaign in 1968 at age 40, unseating the incumbent, Thomas Morris, and becoming the first Republican congressman from New Mexico since 1931.

He held that position continuously for the next 20 years despite major demographic shifts in his constituency.