The Rumsen (also known as Rumsien, San Carlos Costanoan, and Carmeleno) are one of eight groups of the Ohlone, an indigenous people of California. Their historical territory included coastal and inland areas within what is now Monterey County, California, including the Monterey Peninsula. Today, like other Ohlone, Rumsen do not have federal recognition but continue to sustain their culture and community presence in central California.