In 1845, Carson guided Frémont on their third and last expedition. They went to California and Oregon. Frémont made scientific plans, but the expedition was appeared political in nature. Frémont may have been working under secret government orders. President Polk wanted the province of Alta California for the United States. Once in California, Frémont started to rouse the American settlers into a patriotic fever. The Mexican government ordered him to leave. Frémont went north to Oregon. He camped near Klamath Lake. Messages from Washington, DC made it clear that President Polk wanted California.