SANTA FE, N.M. -- Stewart Udall, who sowed the seeds of the modern environmental movement as secretary of the interior during the 1960s and later became a crusader for victims of radiation exposure from the government's Cold War nuclear programs, died Saturday. He was 90.
A statement from Udall's family, released through the office of his son, Sen. Tom Udall, D-N.M., said he died of natural causes at his home in Santa Fe, surrounded by his children and their families.
Udall, brother of the late 15-term congressman Morris Udall, served six years in Congress as a Democrat from Arizona, and then headed the Interior Department for eight years under Presidents Kennedy and Johnson. His son Tom and nephew Mark also became congressmen, then both were elected to the Senate in 2008.
Under Stewart Udall's leadership from 1961 through 1968, the Interior Department aggressively promoted an expansion of public lands and helped win enactment of major environmental laws, including ones to protect endangered species.
President Obama praised Udall's service.
"Whether in the skies above Italy in World War II, in Congress or as secretary of the Interior, Stewart Udall left an indelible mark on this nation and inspired countless Americans who will continue his fight for clean air, clean water and to maintain our many natural treasures," he said.
The current Interior secretary, Ken Salazar, called Udall "one of the greatest secretaries of the Interior in my lifetime."
He "was a pioneer and a visionary in protecting America's natural resources and cultural heritage who exemplified his family's commitment to public service," Salazar said. "Stewart Udall will be greatly missed."