After his defeat at the Battle of Barra in May 1308, King Robert's men chased the forces of rival John Comyn, Earl of Buchan as far as Fyvie Castle.

[9] By the early 14th century, Ireland had not had a recognised High King since Ruaidrí mac Tairrdelbach Ua Conchobair (Rory O'Connor), who had been deposed by his son in 1186.

(In 1258 some of the dynasties and clans had elected Brian Ua Neill to the position of High King; however, he was defeated and killed by the Normans at the Battle of Downpatrick in 1260.)

This became critical when English-backed Scots recaptured the Isle of Man from King Robert's control in January 1315, thereby threatening the south and south-west of Scotland and also reopening up a potential channel of aid to the English from the Anglo-Irish and native Irish.

At about this point, Roger Mortimer, 1st Earl of March, received news from Irish sources that an invasion was about to take place, and made his way to Ireland where he held land, mainly in and around the castle and town of Trim.

(He had previously fought against the Bruces at Bannockburn where he was taken prisoner and freed to return King Edward II's royal seal, lost in the rout.)

In fact, de Brus was never to receive anything more than purely nominal recognition from any of the more powerful Irish kings, and despite entreaties at various times over the next three years, was ignored by those whom he did not directly interest.

In late June, Edward proceeded with his army from Carrickfergus along Magh Line (Six Mile Water), burning Rathmore, near Antrim town, which was a holding of the Savages.

Their attempted ambush ended in their defeat and the army pressed on, destroying de Verdon's fortress of Castle Roche, and on 29 June attacked Dundalk.

While some skirmishing did result in a number of Scots deaths, Edward refused to give battle and instead, with the Ó Néill, retreated northwards to Coleraine via Armagh.

Edward and Domhnall Ó Néill sacked and burned Coleraine, threw down the bridge over the river Bann and faced off de Burgh's pursuing army on the opposite bank.

Mindful of this, de Burgh eventually withdrew back forty miles to Antrim, while Butler had to return to Ormond due to lack of supplies.

In addition to this, Edward sent separate messages both to King Felim and a rival dynast, Cathal Ua Conchobair, promising to support them if they withdrew.

Thus, when in August Edward and his men crossed the Bann in four ships supplied by Scots sea captain, Thomas Dun, de Burgh retreated still further to Connor, where on either the first or ninth of September a charge by the Scots-Irish led to his defeat.

Finally apprised of the seriousness of the situation, Edward II had on 1 September ordered an assembly of the leading Anglo-Irish, which met at Parliament in Dublin in late October, but no decisive action was taken.

At the same time, Governor of Ireland (and Bishop of Ely) John Hotham began to take drastic action to defend Dublin from de Brus, such as leveling entire tenements and churches.

After sacking and burning Kells, Edward proceeded to do the same to Granard, Finnea, the Cistercian monastery of Abbeyleix and raided Angaile (Annaly), the lordship of Gaelic lord O Hanely.

As rule over Ireland had been offered to the Plantagenets by the papal bull Laudabiliter in 1155, Edward's allies, led by Donall O'Neill, sent a remonstrance to Pope John XXII in 1317.

This asked for Laudabiliter to be revoked and informed the Pope that they had chosen Edward as their king: ...we have unanimously established and set him up as our king and lord in our kingdom aforesaid, for in our judgment and the common judgment of men he is pious and prudent, humble and chaste, exceedingly temperate, in all things sedate and moderate, and possessing power (God on high be praised) to snatch us mightily from the house of bondage with the help of God and our own justice, and very willing to render to everyone what is due to him of right, and above all is ready to restore entirely to the Church in Ireland the possessions and liberties...[12]The Papacy neither recognised Edward's claim, nor agreed with the Remonstrance, and his rule remained de facto over parts of Ireland and never de jure over the whole island.