 It partitioned into the lines of Isenburg-Isenburg and Isenburg-Limburg-Covern in 1137, before partitioning again into smaller units, but by 1500 only the lines of Isenburg-Büdingen (in Upper Isenburg) and Lower Isenburg remained.In 1664 the Lower Isenburg branch died out.The Büdingen line continued to partition, and by the beginning of the 19th century the lines of Isenburg-Büdingen, Isenburg-Birstein, Isenburg-Meerholz and Isenburg-Wächtersbach existed.