The female Cistercian monastery of San Andrés de Arroyo had to be founded before 1189, since on that date its abbess, Mencía de Lara, attended the general chapter in Las Huelgas de Burgos. The foundation had the support of Alfonso VIII, who granted the monastery numerous properties and privileges, consolidating its influence in the region of Ojeda (Palencia). Mencía de Lara, of noble lineage, played a key role in the institutional consolidation of the monastery. The monastery increased its patrimony through purchases, donations and exchanges throughout the 13th and 14th centuries. In the 15th century it continued to expand its economic base and to resist feudal litigation, even enjoying the favor of the monarchy (Hernando Garrido, 2002). Unlike other monasteries, San Andrés de Arroyo has maintained continuity in monastic life up to the present day.