Dr. John McLoughlin presided like a feudal king out of Fort Vancouver on the lower Columbia River during the fur-trading era. In the days when the Oregon Territory was governed jointly by the U.S. and Britain, he was the sole governor over an area that covered one-twelfth of the Earth's surface. After an epidemic reached Vancouver in summer 1830, killing 90 percent of the native population, only one person remained who was capable of governing...