John of the Grating was a Cistercian Bishop of Aleth. John was born in Brittany

Brittany

Brittany is a cultural and administrative region in the north-west of France. Previously a kingdom and then a duchy, Brittany was united to the Kingdom of France in 1532 as a province. Brittany has also been referred to as Less, Lesser or Little Britain...

, in 1098 he joined Clairvaux

Clairvaux Abbey

Clairvaux Abbey is a Cistercian monastery in Ville-sous-la-Ferté, 15 km from Bar-sur-Aube, in the Aube département in northeastern France. The original building, founded in 1115 by St. Bernard, is now in ruins; a high-security prison, the Clairvaux Prison, now occupies the grounds...

, where he was professed by St. Bernard

Bernard of Clairvaux

Bernard of Clairvaux, O.Cist was a French abbot and the primary builder of the reforming Cistercian order.After the death of his mother, Bernard sought admission into the Cistercian order. Three years later, he was sent to found a new abbey at an isolated clearing in a glen known as the Val...

. He would go on to found Sainte-Croix de Guingamp and Saint-Jacques de Montfort Abbeys, after his appointment as Bishop

Bishop

A bishop is an ordained or consecrated member of the Christian clergy who is generally entrusted with a position of authority and oversight. Within the Catholic Church, Eastern Orthodox, Oriental Orthodox Churches, in the Assyrian Church of the East, in the Independent Catholic Churches, and in the...

in 1144. He was given the moniker of "Grating", due to the grating , or metal rails, surrounding his shrine.