Karen is on the Chicago, Rock Island and Pacific Railroad and Farm Road 149, two miles north of Mostyn and fifteen miles southwest of Conroe in southwestern Montgomery County. A post office was established in Karen in 1909 and remained in service until 1921. By 1915 the town had a telephone connection, the Bauer sawmill, a wood dealer (J. F. Shannon), and a population of forty; the postmaster at this time was John H. Bauer, who, according to one source, had named the town after his youngest daughter. By 1946 Karen had only two occupied dwellings, located near the railroad station. The town in 1990 consisted of a switch on the railroad, a store, and a few houses.