William Walker (1824-1860) was a United States adventurer in Central America. His armed intervention in Nicaragua gave liberals temporary advantage in their internal war with conservatives and inflamed the slavery controversy in the United States.

William Walker was born in Nashville, Tenn., on May 8, 1824. He earned a medical degree (1843), spent 2 years in Europe, returned, and began a career in law. In New Orleans and, after 1850, in San Francisco, however, he engaged chiefly in newspaper work. A reputation as a crusading journalist and lawyer gave him political potential; but his restlessness and the example of French adventurers who launched from California a colonizing-filibustering venture in Sonora, Mexico, embarked him on another career.

Walker's filibustering began in Mexico. With a small force he invaded Baja California in 1854 and declared that province and Sonora an independent republic, but he was forced to seek refuge in the United States.

A "colonization" contract...