William de Deyn [de la Deyn] (died 1350) was a 14th century Scottish monk and cleric. Little can be said about Deyn's early life. He had obtained a licentiate

Licentiate

Licentiate is the title of a person who holds an academic degree called a licence. The term may derive from the Latin licentia docendi, meaning permission to teach. The term may also derive from the Latin licentia ad practicandum, which signified someone who held a certificate of competence to...

 in decrees at some point in his youth, and he must have become a Tironensian

Tironensian

The Tironensian Order or the Order of Tiron was a Roman Catholic monastic order named after the location of the mother abbey in the woods of Tiron in Perche, some 35 miles west of Chartres in France)...

  monk, for by 1329, and perhaps as early as 1327, he was Abbot of Kilwinning

Abbot of Kilwinning

The Abbot of Kilwinning was the head of the Tironensian monastic community and lands of Kilwinning Abbey, Cunningham , founded sometime between 1162 and 1167. The patron is not known for certain, but it is likely to have been Richard de Morville, Lord of Cunningham...

. Kilwinning Abbey

Kilwinning Abbey

Kilwinning Abbey is a ruined abbey located in the centre of the town of Kilwinning, North Ayrshire.-The establishment of the Abbey:The ancient name of the town is 'Segdoune' or 'Saigtown', probably derived from 'Sanctoun', meaning the 'town of the saint'. Saint Winnings festival was on 21 January...

 was a Tironensian house in Cunninghame

Cunninghame

Cunninghame is a former comital district of Scotland and also a district of the Strathclyde Region from 1975–1996.-Historic Cunninghame:The historic district of Cunninghame was bordered by the districts of Renfrew and Clydesdale to the north and east respectively, by the district of Kyle to the...

, in existence since the 1160s. He appears for the first time in this capacity as witness to a charter

Charter

A charter is the grant of authority or rights, stating that the granter formally recognizes the prerogative of the recipient to exercise the rights specified...

 of Walter Comyn of Rowallan.

In 1344, Deyn, perhaps through Stewart patronage, was chosen to succeed Alexander de Kininmund

Alexander de Kininmund (d. 1344)

Alexander de Kininmund was a 14th century Scottish churchman. The first mention of Alexander occurs when, as a canon of Dunkeld he is one of three ambassadors sent by King Robert I of Scotland to Avignon in 1320. The purpose of this embassy was to present a letter to Pope John XXII known as the...

 as Bishop of Aberdeen

Bishop of Aberdeen

The Bishop of Aberdeen was the ecclesiastical head of the Diocese of Aberdeen, one of Scotland's 13 medieval bishoprics, whose first recorded bishop is an early 12th century cleric named Nechtan...

. Deyn travelled to continental Europe

Continental Europe

Continental Europe, also referred to as mainland Europe or simply the Continent, is the continent of Europe, explicitly excluding European islands....

, and by 27 September had received consecration

Consecration

Consecration is the solemn dedication to a special purpose or service, usually religious. The word "consecration" literally means "to associate with the sacred". Persons, places, or things can be consecrated, and the term is used in various ways by different groups...

. His consecration had been performed by Cardinal Peter Despres. In May 1345, the Pope appointed him as Scotland's papal tax collector, a duty Deyn fulfilled, sending the proceeds to the papacy via merchants in Bruges

Bruges

Bruges is the capital and largest city of the province of West Flanders in the Flemish Region of Belgium. It is located in the northwest of the country....

. He was one of the notables who petitioned the papacy in 1347 to legitimise the marriage of Robert Stewart

Robert II of Scotland

Robert II became King of Scots in 1371 as the first monarch of the House of Stewart. He was the son of Walter Stewart, hereditary High Steward of Scotland and of Marjorie Bruce, daughter of Robert I and of his first wife Isabella of Mar...

 and Elizabeth More of Rowallan. In 1349 he was in attendance with the Justiciar of Scotia

Justiciar of Scotia

The Justiciar of Scotia was the most senior legal office in the High Medieval Kingdom of Scotland. Scotia in this context refers to Scotland to the north of the River Forth and River Clyde....

 holding court at the standing stones of Old Rayne

Old Rayne

Old Rayne is a small village in Aberdeenshire, Scotland, approximately 9 miles north west of Inverurie and 14 miles south east of Huntly along the A96 road.-Etymology:The word "Rayne" comes from the Scottish Gaelic Raon meaning a field of good ground...

 in Garioch

Garioch

Garioch is the name of one of six committee areas in Aberdeenshire, Scotland. It has a population of 46,254 .Centred on Inverurie, a traditional rural market town whose foundation dates back to the 9th century with the establishment of Christianity at Polnar, "The Kirk of Rocharl" - now St...

.

He died on 20 August 1350 and was buried in the choir

Choir

A choir, chorale or chorus is a musical ensemble of singers. Choral music, in turn, is the music written specifically for such an ensemble to perform.A body of singers who perform together as a group is called a choir or chorus...

 of Aberdeen Cathedral.