Saint Aelred of Rievaulx was a 12th-century Cistercian monk and abbot in England. Born around 1110 in Northumbria, he became known for his writings on spirituality, friendship, and the monastic life. Aelred's most famous work, "Spiritual Friendship," emphasizes the importance of deep, loving relationships among individuals seeking God. He became the abbot of the Rievaulx Abbey, a prominent Cistercian monastery in Yorkshire, where he led a community of monks. Aelred's teachings and leadership contributed significantly to the Cistercian reform movement, and he was canonized as a saint in 1200, celebrated for his wisdom and devotion.