The next president, Mirabeau B. Lamar, moved the capital to the new town of Austin in 1839. The first flag of the republic was the "Burnet Flag" (a single gold star on an azure field), followed in 1839 by official adoption of the Lone Star Flag. Internal politics of the Republic centered on two factions. The nationalist faction, led by Lamar, advocated the continued independence of Texas, the expulsion of the Native Americans (Indians), and the expansion of Texas to the Pacific Ocean. Their opponents, led by Houston, advocated the annexation of Texas to the United States and peaceful coexistence with the Indians, when possible. The Texas Congress even passed a resolution over Houston's veto claiming the Californias for Texas. The 1844 presidential election split the electorate dramatically, with the newer western regions of the Republic preferring the nationalist candidate Edward Burleson, while the cotton country, particularly east of the Trinity River, went for Anson Jones. The Comanche Indians furnished the main Indian opposition to the Texas Republic, manifested in multiple raids on settlements, capture, and rape of female pioneers, torture killings, and trafficking in captive slaves. In the late 1830s, Sam Houston negotiated a peace between Texas and the Comanches. Lamar replaced Houston as president in 1838 and reversed the Indian policies. He returned to war with the Comanches and invaded Comancheria itself. In retaliation, the Comanches attacked Texas in a series of raids. After peace talks in 1840 ended with the massacre of 34 Comanche leaders in San Antonio, the Comanches launched a major attack deep into Texas, known as the Great Raid of 1840. Under command of Potsanaquahip (Buffalo Hump), 500 to 700 Comanche cavalry warriors swept down the Guadalupe River valley, killing and plundering all the way to the shore of the Gulf of Mexico, where they sacked the towns of Victoria and Linnville. The Comanches retreated after being pursued by 186 rangers, and were caught at the Battle of Plum Creek wherein they lost the plunder they had taken. Houston became president again in 1841 and, with both Texians and Comanches exhausted by war, a new peace was established. Although Texas achieved self-government, Mexico refused to recognize its independence. On March 5, 1842, a Mexican force of over 500 men, led by Ráfael Vásquez, invaded Texas for the first time since the revolution. They soon headed back to the Rio Grande after briefly occupying San Antonio.