St Mary's Isle Priory was a monastic house of Augustinian

Augustinians

The term Augustinians, named after Saint Augustine of Hippo , applies to two separate and unrelated types of Catholic religious orders:...

 canons

Canon (priest)

A canon is a priest or minister who is a member of certain bodies of the Christian clergy subject to an ecclesiastical rule ....

 located on the Isle of Trail or St Mary's Isle in Galloway

Galloway

Galloway is an area in southwestern Scotland. It usually refers to the former counties of Wigtownshire and Kirkcudbrightshire...

. It is alleged to have originated in an endowment of the island by King Fergus of Galloway

Fergus of Galloway

Fergus of Galloway was King, or Lord, of Galloway from an unknown date , until his death in 1161. He was the founder of that "sub-kingdom," the resurrector of the Bishopric of Whithorn, the patron of new abbeys , and much else besides...

 in favour of Holyrood Abbey

Holyrood Abbey

Holyrood Abbey is a ruined abbey of the Canons Regular in Edinburgh, Scotland. The abbey was founded in 1128 by King David I of Scotland. During the 15th century, the abbey guesthouse was developed into a royal residence, and after the Scottish Reformation the Palace of Holyroodhouse was expanded...

. Whether or not the endowment was made for this purpose, Holyrood Abbey established a daughter house there which is on record by the time of a grant by Lochlann, Lord of Galloway

Lochlann, Lord of Galloway

Lochlann , also known by his French name Roland, was the son and successor of Uchtred, Lord of Galloway as the "Lord" or "sub-king" of eastern Galloway....

 sometime between 1189 and 1193. A "prior of Galloway" by the name of "William" appeared alongside the Abbot of Holywood and his prior in a document preserved by St Andrews Cathedral Priory

St Andrews Cathedral Priory

St Andrews Cathedral Priory was a priory of Augustinian canons in St Andrews, Fife, Scotland. Plans were made for its foundation in the reign of Alaxandair mac Maíl Choluim , who set aside some land for that purpose. It was finally established by King David I and his son in 1140 with canons from...

 dated to 1173, and so it is possible that this William is the earliest recorded Prior of St Mary's Isle

Prior of St Mary's Isle

The Prior of St Mary's Isle was the head of the Augustinian monastic community of St Mary's Isle Priory, in Kirkcudbrightshire, Galloway...

.

The priory maintained its dependent relationship with Holyrood Abbey. In order to help maintain the canons and prior of the monastery, in 1323 King Robert I of Scotland

Robert I of Scotland

Robert I , popularly known as Robert the Bruce , was King of Scots from March 25, 1306, until his death in 1329.His paternal ancestors were of Scoto-Norman heritage , and...

 granted to Holyrood Abbey a tithe of the revenues from royal pleas taken from the area between the rivers Nith

River Nith

The River Nith is a river in South West Scotland.-Source, flow and mouth:The Nith rises in the Carsphairn hills of East Ayrshire, more precisely between Prickeny Hill and Enoch Hill, 7 km East of Dalmellington...

 and Cree

River Cree

The River Cree is a river in Dumfries and Galloway, Scotland which runs through Newton Stewart and into the Solway Firth. It forms part of the boundary between the counties of Wigtownshire and Kirkcudbrightshire....

. The declining health of the priory, related more generally to the declining fortunes of monasteries in Scotland in the 15th century, led James IV of Scotland

James IV of Scotland

James IV was King of Scots from 11 June 1488 to his death. He is generally regarded as the most successful of the Stewart monarchs of Scotland, but his reign ended with the disastrous defeat at the Battle of Flodden Field, where he became the last monarch from not only Scotland, but also from all...

 to seek its reincorporation into Holyrood Abbey. This only led to a kinsman of the abbot of Holyrood becoming Prior of St Mary's Isle. In the 16th century control of the priory was secularized and held by a series of commendators. It came into the control of the Lidderdale family, and formally became part of their entirely secular lordship in 1608.

The peninsula of St Mary's Isle on which the priory stood lies in the estuary of the River Dee

River Dee, Galloway

The River Dee, in south-west Scotland, flows from its source in Loch Dee amongst the Galloway Hills, firstly to Clatteringshaws Loch, then in to Loch Ken, where it joins the Water of Ken. From there, the Dee flows southwards to Kirkcudbright, and into Kirkcudbright Bay to reach the Solway. The...

 south of Kirkcudbright

Kirkcudbright

Kirkcudbright, is a town in Dumfries and Galloway, Scotland.The town lies south of Castle Douglas and Dalbeattie, in the part of Dumfries and Galloway known as the Stewartry, at the mouth of the River Dee, some six miles from the sea...

. It divides the bays of Manxman's Lake and Goat Well Bay. The tidal islet of Inch lies just offshore in Manxsman's Lake.

Robert Burns

Robert Burns

Robert Burns was a Scottish poet and a lyricist. He is widely regarded as the national poet of Scotland, and is celebrated worldwide...

 is said to have composed the "Selkirk Grace" whilst visiting Lord Daer at St Mary's Isle.