IMPERIAL

Imperial County, in the southeastern corner of California, seems at first glance like an improbable subject for a 1,125-page work of nonfiction. Imperial is known for its winter lettuce, its "Sweet Imperial" onions, and the Salton Sea, a polluted saline lake it shares with Riverside; otherwise, it's the kind of landscape where there's so little going on that the Navy uses a great swath of it as an air-to-ground gunnery range. Imperial has played the Kuwaiti desert (in Jarhead) and the desert planet Tatooine in Star Wars. Even the county's Chamber of Commerce can muster only a few facts about it: the county was established in 1907; its highest point is Blue Angel Peak (4,548 feet), its lowest the Salton Sea (a paradoxical 235 feet below sea level). How much, you have to wonder, can there be to say about Imperial?