Cælin was one of four brothers named by Bede

Bede

Bede , also referred to as Saint Bede or the Venerable Bede , was a monk at the Northumbrian monastery of Saint Peter at Monkwearmouth, today part of Sunderland, England, and of its companion monastery, Saint Paul's, in modern Jarrow , both in the Kingdom of Northumbria...

 as active in the early Anglo-Saxon Church. The others were Cedd

Cedd

Cedd was an Anglo-Saxon monk and bishop from Northumbria. He was an evangelist of the Middle Angles and East Saxons in England and a significant participant in the Synod of Whitby, a meeting which resolved important differences within the Church in England...

, Chad

Chad of Mercia

Chad was a prominent 7th century Anglo-Saxon churchman, who became abbot of several monasteries, Bishop of the Northumbrians and subsequently Bishop of the Mercians and Lindsey People. He was later canonized as a saint. He was the brother of Cedd, also a saint...

, and Cynibil

Cynibil

Cynibil was one of four Northumbrian brothers named by Bede as prominent in the early Anglo-Saxon Church. The others were Chad of Mercia, Cedd and Caelin....

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Bede portrays Cælin as a chaplain at the court of Ethelwald, a nephew of King Oswiu of Northumbria

Oswiu of Northumbria

Oswiu , also known as Oswy or Oswig , was a King of Bernicia. His father, Æthelfrith of Bernicia, was killed in battle, fighting against Rædwald, King of the East Angles and Edwin of Deira at the River Idle in 616...

. Ethelwald was appointed to administer the coastal area of Deira. It was on the initiative of Cælin that Ethelwald donated land for the building of a monastery at Lastingham

Lastingham

Lastingham is a village and civil parish which lies in the Ryedale district of North Yorkshire, England. It is on the southern fringe of the North York Moors, five miles north east of Kirkbymoorside, one and a half miles to the east of Hutton-le-Hole. It was home to the early missionaries to the...

 in the North York Moors

North York Moors

The North York Moors is a national park in North Yorkshire, England. The moors are one of the largest expanses of heather moorland in the United Kingdom. It covers an area of , and it has a population of about 25,000...

. The monastery became a base for Cedd, who was serving as a missionary bishop in Essex, and for Chad, who succeeded him as abbot

Abbot

The word abbot, meaning father, is a title given to the head of a monastery in various traditions, including Christianity. The office may also be given as an honorary title to a clergyman who is not actually the head of a monastery...

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