 At this time the Jewish community in Entrena was important, getting to constitute an "aljama", with an approximated population of 50 families.In 1503 "Carlos Ramirez de Arellano" and his wife, "Juana de Zúñiga", gentlemen of Cameros and counts of Aguilar, founded the monastery of Santa Clara in Entrena granting to him in addition the already preexisting "Santa Maria de Barrivero".The founding nuns came from Tordesillas and the monastery belonged to the franciscan province of Burgos.