And 900 years later, as the current heads of the church celebrated his life with a pilgrimage to the abbey set in the heart of the North York Moors, the spirit of St Aelred was present once again within its ancient walls.
More than 120 people, including the Archbishop of York, the abbot and monks from Mount Saint Bernard Abbey, Leicestershire – the last Cistercian monastery in England – and orders of nuns from nearby Wass and Whitby, attended the event to mark the 900th birthday of St Aelred.
The group took part in a five-mile pilgrimage from Helmsley Castle to 12th century Rievaulx Abbey, where St Aelred was the abbot for 20 years, on Saturday, before holding a special service in its grounds.
Tony Powell, 62, an expert in medieval history who has worked for 12 years at the abbey, said: "It was simply superb, the service was beautiful and helped the building come alive.
"We were blessed with the weather with sunlight streaming through the buildings and to hear the Latin chanting echoing from the service was an incredible experience.
"St Aelred's reign was the golden age of the abbey and was when it was at the height of its power, industrial wealth and spiritual influence – it was all brought about because of him.
"He was the foremost theological thinker of his time and was a key instigator in transforming the way communities should live.
"It was a wonderful way to celebrate his remarkable life."
Rievaulx Abbey was founded in 1132 by a group of 12 Cistercian monks who had come from Citeaux, France, in search of solitude.
Aelred, who was born in 1110 at Hexham in Northumberland, first visited the abbey after a stay at Helmsley Castle.
He entered the monastery at the age of 24 and in 1147 became abbot.
After taking the helm at Rievaulx, his commercial acumen coupled with his magnetic spiritual leadership, attracted a devoted following which saw the abbey's population soar to 600, its lands extend as far north as Teesside – and its reputation soar.
His acclaimed spiritual writings, which preached the need for a simpler, less materialistic and more egalitarian way of life, turned him into a national celebrity and he was spiritual advisor to Kings Henry I, Henry II and David I of Scotland.
He died in 1167 after suffering from kidney troubles and acute arthritis. The process to canonise him was begun soon after.
By 1250 a new east end of the abbey's church had been rebuilt and a shrine to St Aelred was built into its walls.
It remained until King Henry VIII dissolved the monastery in 1538, ordering the buildings to be rendered uninhabitable and stripped of any valuables.
Rievaulx Abbey has lain in its current state ever since.
Belinda Heighway, site supervisor at the abbey, said: "We are holding celebrations throughout the year to celebrate the life of St Aelred and this pilgrimage was very special.
"We were delighted to welcome the Archbishop, Dr John Sentamu, and the monks and nuns to the abbey.
"It was a remarkable day."
The 900th anniversary celebrations began during Easter with a dusk candle lighting. A labyrinth walk is also planned and a medieval arts and crafts event.
Another pilgrimage is taking place next week but it is a ticket only event. Call 01439 798 228 for more details.