Henry II of Isenburg-Grenzau was the Count of Isenburg-Grenzau from 1220 until 1287. Henry was a son of Count Henry I, and succeeded him in his Westerwald territories. In 1263 Henry was the first member of the House of Isenburg to be mentioned as being of Grenzau, and over the years he developed Grenzay as a leading castle in the Lower Westerwald. In 1286 Henry divided his realm between his sons. Eberhard, the eldest, was granted Grenzau and surrounding territories. Louis, the middle son, received the territories around Büdingen, and Gerlach, the youngest, received Hönningen. The following year Henry died.