Ewen Cameron, participant in the Mier expedition, was born in Scotland about 1811. He was named for the Scottish hero Sir Ewen Cameron of Lockhiel, laird of Clan Cameron and a staunch supporter of King Charles II. He traveled to Texas during the Texas Revolution and served two terms in the Texas army, the first from April 29 through October 21, 1836. On October 20, 1836, he reenlisted as a private in Capt. Clark L. Owen's Company A of Joseph H. D. Rogers's First Regiment, Permanent Volunteers. He served until the company was mustered out on December 31, 1836. For his service he received bounty warrants for a total of 1,920 acres, which his heirs later claimed in San Patricio County. In the period that followed the revolution he won renown as a leader of the "cowboys" prominent in frontier defense in South Texas. The Telegraph and Texas Register hailed him on September 14, 1842, as "a bold and chivalrous leader" who promised to become "the Bruce of the West."
On July 7, 1842, Cameron took part in the engagement at Lipantitlán against Gen. Antonio Canales. Samuel H. Walker attributed much of the credit for the successful defense of the position to Cameron. At the battle of Mier, "The fearless Cameron, whose company garrisoned the back yard of one of the houses, being charged by an imposing force of the enemy, after emptying his rifles into their lines, beat off the foe until he could reload, with the loose stones in the court." At Pass Suarte, after Fisher and the staff officers had been separated from the command, the Mier prisoners unanimously chose Cameron as their commander. On Saturday, February 19, Cameron and about sixty men were recaptured by Mexicans and subjected with other groups to the Black Bean Episode. Cameron drew a white bean in the lottery, but was shot for a later attempt at escape. The town of Cameron, Texas, county seat of Milam County was named for Ewen Cameron in 1846, and Cameron County was named in his honor.