The Rangers continued to participate in skirmishes with Native Americans through 1846, when the annexation of Texas to the United States and the Mexican–American War saw several companies of Rangers mustered into federal service. They played important roles at various battles, acting as guides and participating in counter-guerrilla warfare, soon establishing a fearsome reputation among both Mexicans and Americans. At the Battle of Monterrey in September 1846, famous Texas Rangers such as John Coffee "Jack" Hays, Ben McCulloch, Bigfoot Wallace and Samuel Hamilton Walker played important roles in the battle, including advising General William Jenkins Worth on the tactics required to fight inside a Mexican city. Richard Addison Gillespie, a famed Texas Ranger, died at Monterrey, and General Worth renamed a hill "Mount Gillespie" after him. Colonel Hays organized a second regiment of Texas Rangers, including Rip Ford, who fought with General Winfield Scott in his Mexico City Campaign and the Anti-guerrilla campaign along his line of communications to Vera Cruz.