The Barony of Eaglesham (1158, Egilsham; 1309, Eglishame) formed part of the grant made by
David I (1124–53) to
Walter fitz Alan, the founder of the house of Stewart. Eaglesham may well have come into the possession of the Montgomery family during Walter's floruit, since the family were certainly lairds of Eaglesham at a later date, and a certain Robert of Montgomery was one of Walter's prominent tenants. ) John de Montgomery and his brother are listed on the
Ragman Roll, rendering homage to
Edward I of England for their estates in 1296. A later Sir John, the ninth Laird or Baron of Eaglesham, was one of the heroes of the
Battle of Otterburn in 1388, capturing
Sir Henry Percy, nicknamed 'Hotspur' in single combat and holding him ransom. Sir John's mother was a Douglas and a long term feud had existed between the Percy and Douglas families. Ransoming important captives was the custom in the 14th century and Sir John used the money paid over by the English for the release of Hotspur to build himself a fine castle at Polnoon. It is said that following the chivalrous treatment of his captive, Sir John gained the lasting friendship and admiration of Sir Henry Percy and that he may have even assisted in the technical design and construction of the fortifications. The ballad of the 'Battle of Otterburne' commemorates the events of 1388 that led to these developments: Sir Hugh Montgomery, the son of this Sir John, was slain at the Battle of Otterburn by an arrow fired by an English archer as recorded in
The Ballad of Chevy Chase: Hugh's body was carried to Edinburgh Castle, together with the trophies of Percy's spear and pennon. These have remained with the Montgomery family to the present day (2013). Hugh's body was taken for burial to his home lands and his coffin now lies in the
Skelmorlie Aisle of Largs Old Kirk at
Largs in North Ayrshire. John, seventh baron of Eaglesham's daughter married Archibald Mure of
Rowallan Castle and their great-grand-daughter Elizabeth married King
Robert II. In the fourteenth century the baronies of
Eglinton and
Ardrossan were obtained by the marriage in 1368 of John de Montgomery with Elizabeth, daughter and heiress of Sir Hugh Eglinton, by a half-sister (Robert and Egidia share the same father, but have different mothers), Egidia, of
Robert II, King of Scotland.
The name One suggestion is that the name Polnoon is a corruption of the old Scots word 'poinding', meaning a ransom, however the word 'Pol' may instead refer to a pool in a river, such as is present below Polnoon's site. Punone is the name applied in a 19th-century Montgomery family history. Buchan has is as 'Punoon' in 1840.
The castle's position and layout Illustrations of the castle are scarce, however
John Ainslie's 1799 survey of the Eglinton Estates includes a vignette of the Polnoon Castle ruins.
Timothy Pont's map as published by
Johan Blaeu in 1654 illustrates Polnoon as a central single-storey house with a flanking building on each side, joined to the centre by a fence-like structure. The motte lies about a mile south of Eaglesham church, sitting on a promontory with views of the surrounding countryside. The mound is rectangular, 30 by 22 m base, 18 by 10 m top, at least 4 m high and may have been built for an earlier castle of the Montgomerys, for the later structure encased the castle mound itself. The north-west corner of the tower, and the north range rise from the bedrock 3m below the base of the motte. On the east side are indications of a ditch that ran across the promontory. The main entry to Polnoon may have been to the east of the enclosure as the range on the south extends in that direction. The castle remains do show signs of post-medieval use, possibly as a free-standing dwelling. There are traces of a battered
plinth along the south wall. record the castle name as 'Palnoon' and only refer to the site, describing it as ''strongly sited on the summit of a steep conical mound'...and ..'fragments on masonry here and there.'' Today (2009) large chunks of masonry appear almost randomly scattered across the site and in the Polnoon Water; very little remains in place as recognisable structures. On the west side, the ground falls steeply to the Polnoon Water, which forms a confluence with the
White Cart nearby. There is no sign of a bailey or outworks on the east. The unusually chaotic condition of the masonry prevents any clear attempt at a plan of the ruins. At the northwest corner of the mound is the angle of what must have been a massive wall. At the base of the slopes at the southeast end is a stretch of walling 1.6 m thick, possibly part of a courtyard wall. The quarter panels on the Eglinton Castle example are a mirror image of the standard Montgomerie coat of arms, the only other example noted of this arrangement is that to be found above the entrance and on the ceiling of the
Skelmorlie Aisle of Largs</a> Old Kirk, belonging to Sir Robert Montgomerie, conjoined with those of his wife, Margaret Douglas. The reason for this heraldic arrangement is unknown; it may be a simple error as in the
Stanecastle armorial panel which is upside down. The old castle doors are recorded as being in the 'Edinburgh Museum', a stone from the castle bearing a Masonic symbol is in use as a gravestone in the churchyard and a piece of furniture is in the Glasgow Art Gallery. In heraldic terms the full Montgomerie arms are described :
Quarterly, 1st & 4th grand quarters, counterquartered, Azure three fleurs-de-lis Or (Montgomerie); & three annulets Or, stoned Azure (Eglinton); all within a bordure Or charged with a double tressureflory counterflory Gules;2nd & 3rd grand quarters, counterquartered, Or, three crescents within a double tressure flory counterflory Gules (Seton); Azure, three garbs Or (Buchan), overall an escutcheon parted per pale Gules and Azure, the dexter charged with a sword in pale Proper, pommelled and hilted Or, supporting an imperial crown, the sinister charged with star of twelve points Argent, all within a double tressure flory counterflory Gold. ;Views at Polnoon Castle File:Mound at Polnoon Castle.JPG|Polnoon Castle motte File:Stone course - Polnoon Castle.JPG|A masonry course still in situ File:Fallen masonary Blocks - Polnoon Castle.JPG|Masonry blocks File:Polnoon Castle - fallen masonary.JPG|Large masonry block with mortar File:Polnoon Castle - isolated masonary.JPG|An isolated block File:Polnoon Burn - Millhall.JPG|The Polnoon Burn from the motte File:Polnoon Castle from the burn.JPG|Polnoon Castle from below File:Mill at Millhall - Eaglesham.JPG|Millhall Mill from Polnoon Farm ==The murder of the 4th Earl of Eglinton==