The history of Yosemite National Park is as compelling as the waterfalls, monoliths, and peaks that have mesmerized visitors for more than a century. But what hikers see today in the iconic Yosemite Valley, as well as on the peaks in the high country and within the Mariposa Grove of Big Trees, is a world away from the place Native Americans once called Ahwahnee, and from what gold-seekers and mountain men looked upon in the park's earliest days. Historic...