Tennessee is known as the "Volunteer State", a nickname some claimed was earned during the War of 1812 because of the prominent role played by volunteer soldiers from Tennessee, especially during the Battle of New Orleans. Other sources differ on the origin of the state nickname; according to the Columbia Encyclopedia, the name refers to volunteers for the Mexican–American War. This explanation is more likely, because President Polk's call for 2,600 nationwide volunteers at the beginning of the Mexican-American War resulted in 30,000 volunteers from Tennessee alone, largely in response to the death of Davy Crockett and appeals by former Tennessee Governor and now Texas politician, Sam Houston.