Somerset County is the southernmost county in the U.S. state of Maryland. As of the 2020 census, the population was 24,620, making it the second-least populous county in Maryland. The county seat is Princess Anne. The county is part of the Lower Eastern Shore region of the state. The county was named for Mary, Lady Somerset, the wife of Sir John Somerset and daughter of Thomas Arundell, 1st Baron Arundell of Wardour.