Warren is a city in and the county seat of Trumbull County, Ohio, United States. The municipality is located in northeastern Ohio, approximately 14 miles northwest of Youngstown and 56 miles southeast of Cleveland.
The population was 41,558 at the 2010 census. Warren is the second largest city in the Youngstown-Warren-Boardman, OH-PA Metropolitan Statistical Area, and anchors the northern part of that area.