Former Interior Secretary Stewart Udall, who in the 1960s helped kick-start the environmental movement and fought for people who’d been hurt by Cold War- era nuclear programs, died Saturday at the age of 90. Udall died of natural causes at his home in Santa Fe, New Mexico, his family said. Udall came from a storied political family—he was the brother of 15-term congressman Morris Udall and father of Tom Udall and uncle to Mark Udall, both elected to the Senate two years ago. He served six years himself as a Democratic representative of Arizona before working for the Kennedy and Johnson administrations. Udall fathered several important pieces of environmental legislation, growing public parks and protecting endangered species. "If in our haste to 'progress,' the economics of ecology are disregarded by citizens and policymakers alike, the result will be an ugly America," Udall wrote in 1963. "We cannot afford an America where expedience tramples upon aesthetics and development decisions are made with an eye only on the present." In the late 1970s, Udall sued the government on behalf of Navajo men who got lung cancer after working in uranium mines for the government. He also sued to help Nevadans who lived downwind from nuke tests conducted in their state after World War II. He was key in the eventual passage of a law that compensated radiation victims.