Duntreath is known to have been part of the Lennox by the mid 14th century. Donald Earl of Lennox, died before 1370, but a charter, referring to land held by him, is in the possession of Lord Napier. This charter, dated 9th February 1408, made by his grandson, Donald Earl of Lennox, granted the lands of Duntreath to his brother Murdoch. The document (translated from Latin) 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.

The word "monte" is taken to refer to what used to be known as "the Court Hill," now Park Hill, which rises on the east side of the Blane Valley opposite to Dumgoyak (sik). The top has been levelled, possibly for a fort, or a "mons placiti" or Moot Hill where courts of justice were held. The feudal privileges attached to Duntreath, indicate its importance.

The Edmonstones of Duntreath descend from Archibald, believed to have been the second son of the first Sir John Edmonstone, and therefore brother of the second John, who married Isabella, daughter of Robert II. Isabella's brother, also named Robert, became Robert III in 1390, but because of physical and mental debility, he was supplanted as ruler. His heir the Duke of Rothesay, and his brother, the Duke of Albany (the first two dukes in Scotland) were given control of the government.

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". Then in the following year the King accepted the challenge of Robert Morley, an English knight, that he would take a golden cup from his table unless prevented by a Scottish knight. Morley was defeated in this purpose by James Douglas of Strabnock. 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. The Englishman "got the worst of it" and Archibald Edmonstone may have received his knighthood in reward.

In 1406 King Robert was a desperate man. His eldest son, David Duke of Rothesay, had almost certainly been murdered with his brother Albany's connivance, and now his surviving son James, a boy of twelve years old, was all that stood between Albany and the throne.

The King, frantic to save James, secretly made arrangements for him to go to France. Leaving the Royal Castle of Rothesay 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.

There he was joined by an escort of men his father could trust, amongst them Sir Archibald Edmonstone. 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. It seemed that they had escaped but, on March 22nd, as she rounded Flamburgh Head, the ship was captured by a band of pirates led by one Hugh-atte-Fen.

They sailed her down to London where a delighted Henry IV rewarded them with her cargo. Prince James was sent to the Tower, but the English, unwilling to provide for Scottish prisoners, apparently released his escort.

King 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.

(Register House., State Papers. No. 12.)

King James I, as he now was, returned to Scotland in 1424. His uncle Albany was now dead, but by an Act of Parliament of March 1425, he tried and executed Albany's heir, Murdoch Duke of Albany, together with all but one of his sons and his aged father-in-law, the Earl of Lennox. He then distributed their forfeited lands to his supporters, who included William, son of Sir Archibald Edmonstone.

An entry in the Chamberlain's Rolls in the Compota Ballivorum ad extra, under the head of the Earldom of Lennox, dated 1434, states that the Bailiff of the Crown "non onerat se de fermis terrarum de Erlelevin (Arlehaven), Drumfyn, (Dumfoin), et Duntreyne (Duntreyve, or Duntreath),...quia Rex William de Edmonstone de eisdem." (because the King has infeft William Edmonstone in them.)

Sir William Edmonstone, Ist of Duntreath, is styled of Culloden, (land near Inverness acquired from the Setons, a further indication of relationship). In 1425 he married the Princess Mary, sister of James I and widow of the Earl of Angus, as her fourth husband. Although probably in her late thirties she bore him a son and a daughter. She is buried in Strathblane church.