Complex sentence: Toward the end of the 17th century an owner of Kasteel Duivenvoorde, Johan, retook the name of van Wassenaar Therefor, though the same family remained to live in the House, this was ow under a different name.
Split into simpler sentences: Toward the end of the 17th century an owner of Kasteel Duivenvoorde, Johan, readopted the name of van Wassenaer. Therefore, although the same family remained in the House, this was under a different name.