 Indeed some egyptologists believe that by the end of Ay's reign the 13th dynasty had lost control of Lower Egypt, including the Delta region and possibly Memphis itself.For these authors, this marks the end of the Middle Kingdom and the beginning of the Second Intermediate Period.This analysis is rejected by Ryholt and Baker however, who note that the stele of Seheqenre Sankhptahi, reigning toward the very end of the 13th Dynasty, strongly suggests that he reigned over Memphis.