Question: The seat of Alexanders of Menstrite, a sept of Clan MacAlister of Scotland, is at a castle in Clackmannanshire, that was at one time owned by a family who were created Baronets of Menstire in what year?

Context articles: Menstrie Castle
Clan MacAlister
Loup House
Saint Margaret of Scotland
Clan MacAlister of Antrim
Alexanders of Menstrie
Alasdair Mór
Eachann Mac Goraidh MacAlasdair
Charles Somerville MacAlester
Goraidh Mac Eachann MacAlasdair

Menstrie Castle is a three-storey manor house in the town of Menstrie, Clackmannanshire, near Stirling, central Scotland.
 From the early 17th century, it was home to Sir William Alexander, 1st Earl of Stirling, who was instrumental in founding the colony of Nova Scotia.
 It was later owned by the Holburn or Holborne family, who were created Baronets of Menstrie in 1706.
 The castle was restored in the 20th century, won a Civic Trust award, and now incorporates holiday accommodation, private flats, and a museum and cafe run by the National Trust for Scotland.
Clan MacAlister is a Scottish Clan and a branch of Clan Donald.
 The clan is the earliest branch to have split off from Clan Donald, claiming descent from Alasdair Mòr, son of Domhnall founder of Clan Donald.
 From Alasdair Mòr the clans takes its surname "MacAlister"; this surname is an Anglicisation of the Gaelic "MacAlasdair" meaning "son of Alasdair".
 In the 15th century the chief of the clan was seated in Kintyre, and the clan was centred there until the 18th century, when a chief sold the family estate in preference to a lowland estate.
Loup House is a manor house north of Clachan on the Kintyre peninsula of Argyll, Scotland.
 The estate was once home to the chiefs of Clan MacAlister, and the chief still takes the name "MacAlester of Loup".
 Sir William Mackinnon purchased the estate in 1867.
Saint Margaret of Scotland (c. 1045 – 16 November 1093), also known as Margaret of Wessex, was an English princess of the House of Wessex.
 Margaret was sometimes called "The Pearl of Scotland".
 Born in exile in the Kingdom of Hungary, she was the sister of Edgar Ætheling, the shortly reigned and uncrowned Anglo-Saxon King of England.
 Margaret and her family returned to the Kingdom of England in 1057, but fled to the Kingdom of Scotland following the Norman conquest of England in 1066.
 In 1070 Margaret married King Malcolm III of Scotland, becoming Queen of Scots.
 She was a very pious Roman Catholic, and among many charitable works she established a ferry across the Firth of Forth in Scotland for pilgrims travelling to St Andrews in Fife, which gave the towns of South Queensferry and North Queensferry their names.
 Margaret was the mother of three kings of Scotland, or four, if Edmund of Scotland, who ruled with his uncle, Donald III, is counted, and of a queen consort of England.
 According to the "Vita S. Margaritae (Scotorum) Reginae" ("Life of St. Margaret, Queen (of the Scots)"), attributed to Turgot of Durham, she died at Edinburgh Castle in Edinburgh, Scotland in 1093, merely days after receiving the news of her husband's death in battle.
 In 1250 Pope Innocent IV canonized her, and her remains were reinterred in a shrine in Dunfermline Abbey in Fife, Scotland.
 Her relics were dispersed after the Scottish Reformation and subsequently lost.
 Mary, Queen of Scots at one time owned her head, which was subsequently preserved by Jesuits in the Scottish College, Douai, France, from where it was subsequently lost during the French Revolution.
Clan MacAlister of Antrim is an Irish clan and a branch of Clan MacAlister of Scotland.
 The clan was established as an Irish sept in Antrim in north-east Ulster, as gallóglaigh (galloglasses), in the service of the Lord of the Isles and Clan MacDonald of Dunnyveg.
The Alexanders of Menstrie, also known as the House of Alexander, are a sept of Clan MacAlister of Scotland, itself a branch of Clan MacDonald.
 The family is said to descend from Somerled, Lord of the Isles.
 The seat of the clan was at Menstrie Castle in Menstrie, Clackmannanshire.
 Descendants of the Alexanders of Menstrie have become prominent in Ireland, England and the United States.
Alasdair Mór mac Domhnaill was a younger son of Domhnall mac Raghnaill—the eponymous ancestor of Clan Donald.
 He first appears on record in 1253, when it is recorded as witnessing a charter by his brother, Aonghus Mór, to Paisley Abbey.
 According to the 19th century Clan Donald historians Angus and Archibald Macdonald, Alasdair Mór must have been a prominent man as he is the only recorded brother of Aonghus Mór.
 He is recorded in the Annals of Connacht, in the year 1299, as being a man noted for being a "generous and bounteous man".
 In that year he was slain in a conflict with Alasdair of Argyll and the MacDougalls.
 He is said to have had at least five sons: Dòmhnall, Gòraidh, Donnchadh, Eoin and Eachann.
 Alasdair Mòr was succeeded in the representation of his clan by Dòmhnall.
 Today he is considered to be the eponymous ancestor of Clan MacAlister.
Eachann Mac Goraidh MacAlasdair (English: Hector, son of Goffrey, son of Alexander , anglicised: "Hector MacGorrie MacAlester"), was the 6th of Loup, Chief of Clan MacAlister.
 He succeeded to the title in 1636.
 He was hanged for treason at Whinny Hill, Kinlochkerran, Scotland in 1647.
Lieutenant-Colonel Charles Somerville MacAlester of Loup and Kennox (1797–1891) was a son of Charles MacAlester and Janet Somerville.
 He was born in Scotland in 1797 and was a chief of Clan MacAlister.
Goraidh Mac Eachann MacAlasdair (English: Geoffrey son of Hector, son of Alexander , anglicised "Godfrey MacEachan MacAlester", or "Gorrie") was born c. 1570-1580s, he became 5th of Loup, Chief of Clan MacAlister in 1587.
 He died in c. 1636 at Tarbert, Argyll, Scotland.