Its county seat is Brownsville.The county was founded in 1848 and is named for Captain Ewen Cameron, a soldier during the Texas Revolution and in the ill-fated Mier Expedition. As of the 2010 census, its population was 406,220. Some of the cities, towns, and places in Cameron County are Arroyo City, Arroyo Colorado Estates, Arroyo Gardens, Bayview, Bixby, Bluetown, Boca Chica Village, Brownsville, Cameron Park, Chula Vista, Combes, Del Mar Heights, El Camino Angosto, Encantada-Ranchito-El Calaboz, Grand Acres, Green Valley Farms, Harlingen, Iglesia Antigua, Indian Lake, Juarez, La Feria, La Feria North, La Paloma, La Tina Ranch, Lago, Laguna Heights, Laguna Vista, Las Palmas II, Lasana, Laureles, Los Fresnos, Los Indios, Lozano, Olmito, Orason, Palm Valley, Port Isabel, Primera, Rancho Viejo, Rangerville, Ratamosa, Reid Hope King, Rio Hondo, San Benito, San Pedro, Santa Maria, Santa Rita, Santa Rosa, Solis, South Padre Island, South Point, Tierra Bonita, Villa del Sol, Villa Pancho, YznagaĬameron County, officially the County of Cameron, is the southernmost county in the U.S.