The Norse sagas describe him as successful in extending his realm over the Baltic Sea, but unsuccessful in his attempts of westward expansion.
After the Danish conquest of England in 1016, King Canute the Great had the infant son of Margaret; prince Edward of Scotland exiled to the continent.
They carried his instructions to intercede with Charles V to influence the Pope and Cardinals on behalf of Margaret Logie (widow of David II) in a suit to be brought before the papal court.
In 1381 a passport was issued to John de Edmonstone with 16 men and 16 horses, to make a pilgrimage to the Holy Land, while another for the following year permitted their return.
The date of his death, and likewise the identity of his wife, are unknown, but records show that he was succeeded by his eldest son, also named John.
A charter, dated 9 February 1408, made by Donald Earl of Lennox, granted the lands of Duntreath to his brother Murdoch.
The document states that Donaldus de Lefnax (Lennox) living at Catter, near Buchanan, confirmed Murdacho de Lefnax, his brother, in the land of "Dumgoyak cum reddyng una cum monte que vocatur Duntreth," and other lands of Blargin and of Dumfyn in the Lennox, for the heritable reddendo of a pair of white spurs yearly.
In 1398 Queen Anabella, wife of Robert III, "instituted a great hastitudium (passage of arms) of twelve knights, of which the chief was David Duke of Rothesay, on the north of Edinburgh".
Mortified he rode south to Berwick, where he engaged in single combat on the same day with two Scottish knights, one Hugo Wallace and the other Archibald Edmonstone.
Leaving Rothesay Castle on Bute, supposedly for St Andrews, to continue his education at the College, he was taken instead to North Berwick, and rowed out to the Bass Rock.
At last, after a month, a merchant ship the Maryenknyght of Danzig, her master a Captain Bereholt, with a cargo of wool and hides, sailed down from Leith and took James and his retinue aboard.
Prince James was sent to the Tower of London, but the English, unwilling to provide for Scottish prisoners, apparently released his escort.
Robert III died of shock on news of his son's capture, and Albany became Regent during the young King's captivity which lasted for eighteen years.
In I4II Sir Archibald Edmonstone was one of two visitors who carried back letters to Albany and the Scottish Estates, begging them to negotiate his release.
On 20 July 1593 the Laird of Tullibardine hit William Edmondstone of Duntreath in the face with the hilt of his sword during a session of the Parliament in the Tolbooth of Edinburgh, in the presence of James VI.
Four years later, in 1786, Lyle sold the western part, called West Arlehaven, or Meadowhead, to Sir Archibald Edmonstone, 1st Bt.
The Spittal of Ballewan, a small acreage of land on the western side (now known as the High Haggles Field), is believed to have been granted by one of the Earls of Lennox to the Knights Templars.
It first appears in the writs of Duntreath when a charter of alienation of "The Temples Lands of the Hospital of Ballewan" was given by John Blair and others to James Edmonstone of Broich.
The deed narrates "That the said Archibald Edmonstone and his heirs for ever shall have that east third part near the lands of Duntreath beginning from the burn of Croftelan, descending to the Water of the Blane by the ridge where the oak grows."
This oak, known as "The Meikle Tree", which stood by the roadside at Blairquhosh, was a favourite trysting place both for peaceful purposes and for the assembling of the Strathblane branch of the Clan Buchanan in times of war.
In 1614 Thomas Buchanan of Carbeth sold them to Sir William Livingston of Kilsyth, who had a wadset, (security against a loan) of the estate of Duntreath.
The matter was completed by a charter from King Charles I, dated 28 June 1632, upon the resignation of William Livingston, erecting in favour of Archibald Edmonstone, the parts of the Barony of Duntreath which were redeemed and the lands of the Lettre (sic) into a free Barony for ever, as in the charter of King James II, 1452, to be held in free blench farm.
By the beginning of this century however, Middleton had ceased to be a farm and the house was rebuilt and enlarged by Sir Archibald Edmonstone, 5th Bt., for his sister Lady Dunedin.
In 1956, on the inheritance of the present laird, his mother Gwendolyn, the dowager Lady Edmonstone, moved into the "Lettre Cottage", as it then was called, where she lived until she died in 1989.
The hill of the Ibert was then included in the Lettre sheep farm while the lower ground until recently, carried a herd of dairy cows.
The conical wooded hill of Dumgoyach (composed of basalt volcanic rock which survived the erosion of the ice age) stands to the south west.
Now thanks to extensive draining by the present laird and his father, this ground is sound enough to be used for equestrian events, but once it proved a deterrent to enemies aimed upon attack.
(1776?-1841) who followed his profession, entered the army and served under Sir Ralph Abercromby in Egypt before returning to Lerwick to succeed to his father's practice.
Laurence's eldest son, Thomas Edmondston (1825-1846) born at Buness in Unst, became well known as a naturalist and was elected to the professorship of Botany and Natural History in Anderson's "University" at Glasgow in 1845.
The ship having anchored off the coast of Peru, a boat was sent ashore, but on re-embarking a rifle was accidentally discharged and the ball, passing through Edmondston's head, killed him instantaneously.