(Latin: Aelredus Riaevallensis), also known as also Ailred, Ælred, or Æthelred; (1110 – 12 January 1167) was an English Cistercian monk and writer who served as Abbot of Rievaulx from 1147 until his death.

Aelred spent several years at the court of King David I of Scotland in Roxburgh, possibly from the age of 14,[4] rising to the rank of echonomus[5] (often translated "steward" or "Master of the Household").

Cistercian abbots were expected to make annual visitations to daughter-houses, and Rievaulx had five in England and Scotland by the time Aelred held office.

The fourteenth-century version of the Peterborough Chronicle states that Aelred's efforts during the twelfth-century papal schism brought about Henry II's decisive support for the Cistercian candidate, resulting in 1161 in the formal recognition of Pope Alexander III.

[18] Walter reports that in 1157 the Cistercian General Council allowed him to sleep and eat in Rievaulx's infirmary; later he lived in a nearby building constructed for him.

[20] On top of its intellectual foundation, Aelred draws on his personal experience to provide "specific and concrete"[21] recommendations for creating and maintaining long-term friendships.

According to Brian McGuire, "Aelred believed that true love has a respectable name and a rightful place in good human company, especially that of the monastery.

In writing a special treatise dedicated to friendship and indicating that he could not live without friends, Aelred outdid all his monastic predecessors and had no immediate successors.

We mean then by the 'good' those whose actions and lives leave no question as to their honour, purity, equity, and liberality; who are free from greed, lust, and violence; and who have the courage of their convictions.

[26] In writing of adolescent friendship Augustine said, "For I even burnt in my youth heretofore, to be satiated in things below; and I dared to grow wild again, with these various and shadowy loves: my beauty consumed away, …pleasing myself, and desirous to please in the eyes of men.

In the Prologue however, he mirrors Augustine's description of his early adolescence with the speaker describing his time at school, where "the charm of my companions gave me the greatest pleasure.

"[28] Jocelyn of Furness, writing about Aelred after his death, described him as "a man of the highest integrity, of great practical wisdom, witty and eloquent, a pleasant companion, generous and discreet.

[37] Within this context, "there is a movement among priests and religious who consider themselves to be gay in their sexual orientation to find in historical figures such as Aelred earlier expressions of their own identity.

[42] Ruth Mazo Karras, as the expert in medieval gender and sexuality, cites Aelred as an example of a man "for whom same-sex erotic relationships, even if chaste, were important.

"[43] She also states that "depictions of a Middle Ages concerned only with spiritual issues as opposed to material, a culture whose people were so radically different from us that their bodies became irrelevant, have been superseded by recent scholarship.

Two years later, Integrity canonized Aelred as their official patron, promising "to regularly observe his feast, promote his veneration and seek before the heavenly throne of grace the support of his prayers on behalf of justice and acceptance for lesbians and gay men.

[42] McGuire notes that "in the Life of Waldef, there is a colorful story about how a woman tried to tempt the budding Cistercian saint into bed, and how he resisted her.

Knowles, a historian of monasticism in England, also described him as "a singularly attractive figure," saying that "No other English monk of the twelfth century so lingers in the memory.