The Battle of Moyry Pass begins on September 20, 1600, ending on October 9, in counties Armagh and Louth, in the north of Ireland, during the Nine Years’ War. It is the first significant engagement of forces following the cessation of arms agreed in the previous year between the Irish leader Hugh O’Neill and the English Crown commander, Robert Devereux, 2nd Earl of Essex.

The battle is fought by the armies of O’Neill and Charles Blount, 8th Baron Mountjoy, a follower of the late Earl of Essex. Mountjoy is determined to pierce O’Neill’s heartland in central and western Ulster by the Moyry Pass. In the course of the two-week assault the English troops establish a garrison near Armagh, taking heavy casualties, and Mountjoy retires with difficulty to Dundalk.

Mountjoy’s strategy for putting down O’Neill’s rebellion is gradually to constrict his territory in Ulster with a ring of fortified garrisons on the borders. To this end, he lands seaborne forces at Derry in the north of the province and at Carrickfergus in the east of Ulster. In September 1600, Mountjoy moves north from Dublin and concentrates at Dundalk in order to mount an expedition further into Ulster and re-establish a garrison at Armagh, which position had been evacuated by the English Crown forces after O’Neill’s victory at the Battle of the Yellow Ford in 1598.

On September 17, 1600, Mountjoy sets out from Dundalk, intending to march to Newry and then on to Armagh. The Moyry Pass (or “Gap of the North”) is the sole point of entry to Ulster as much of the terrain is wooded and mountainous, and it has been well fortified by O’Neill with trenches and barricades. There are three lines of trenches, barricaded with earth and stone, and on the flanks the Irish have made further earth and stone works and “plashed” (twisted) the branches of low-growing trees in order to provide cover for themselves and prevent the English occupying the heights on either side of the Pass.

The English reach the pass on September 20 and set up camp just outside, to the south on Faughart Hill. Taking advantage of a misty day on the 25th, an officer named Thomas Williams (who had commanded the Blackwater Fort during the Battle of the Yellow Ford) makes a sortie into the pass. After heavy fighting he identifies the Irish defence works and returns to the English camp with 12 dead and 30 wounded. For six days heavy rain holds up the fighting, until the weather clears on October 2. The weather is important because the matchlock muskets of the day do not work in wet conditions. On October 2, Sir Samuel Bagnall leads his regiment of infantry into the Pass at the head of four other regiments. The English breach the first barricade, and Thomas Bourke’s regiment leads the way to the second and third lines of defence. The English take the second line only to find themselves in a trap, with gunfire concentrated from three sides. They try to dislodge the Irish from their remaining positions for three more hours before retreating, with the Irish in close pursuit. The English admit 46 killed and 120 wounded, but it is thought that they understated their losses throughout the campaign.

On October 5, Mountjoy sends two regiments on a flanking march over the hill to the west, with one further regiment supported by horsemen advancing up the centre of the Pass. No significant gains are made, and the regiments turn back, reporting casualties of 50 dead and 200 wounded.

By October 9 the privy councilor Geoffrey Fenton complains, “we are now but where we were in the beginning.” Mountjoy retires to Dundalk on either October 8 or 9, but on October 14 word reaches the English camp that O’Neill has abandoned the Pass and retreated to a crannog stronghold at Lough Lurcan. The most likely explanation for O’Neill’s withdrawal from his position of strength is that he is short of ammunition and food and fears a flanking attack on his rear from Newry.

Mountjoy occupies the Moyry Pass on October 17 and dismantles O’Neill’s earthworks. He marches on to Carrickban, just outside Newry, and by Sunday, November 2, sets up camp at Mountnorris, halfway between Newry and Armagh. There he builds an earthwork fort and leaves a garrison of 400 men under the command of Captain Edward Blaney. He then marches back to Dundalk via Carlingford, but is attacked on November 13 by O’Neill, close to the Fathom Pass. Mountjoys men force their way through, and the Lord Deputy claims the army lost 15–20 killed and 60–80 wounded, but a later report suggests the losses are much heavier, with 80 killed.

The battle of Moyry Pass is a stalemate as Mountjoy cannot take the Pass and O’Neill cannot keep it. Mountjoy does establish a garrison at Mountnorris, but has to retire to Dundalk after taking substantial casualties. Mountjoy claims his force lost only 200 men killed and 400 wounded in the fighting from September 20 to November 13, though this may be a considerable underestimate. More, he says, died of disease. The Irish casualties are given by the English as an incredible 900–1,200 killed and wounded, but this is questionable given that the Irish were in a strong defensive position of their own choosing, behind the protection of fieldworks. These figures probably say more about what Mountjoy wanted Queen Elizabeth I to hear than about the actual casualty figures. The following year Mountjoy builds Moyry Castle to secure the pass.

(Pictured: View of the entrance to the Moyry Pass looking north from Faghart Hill)