The Battle of Knockavoe was fought in 1522 between the O'Donnell

O'Donnell dynasty

O'Donnell , which is derived from the forename Domhnaill were an ancient and powerful Irish family, kings, princes, and lords of Tír Chonaill in early times, and the chief allies and sometimes...

s, led by Hugh Dubh O'Donnell and Manus O'Donnell

Manus O'Donnell

Manus Ó Domhnaill, anglicized Manus O'Donnell , was an Irish clan leader, son of Hugh Dubh O'Donnell. He was an important member of the O'Donnell dynasty based in County Donegal.-Early life:...

, against the O'Neill

O'Neill dynasty

The O'Neill dynasty is a group of families that have held prominent positions and titles throughout European history. The O'Neills take their name from Niall Glúndub, an early 10th century High King of Ireland from the Cenél nEógain...

s, in which the O'Neills and their supporters were surprised and routed. Not a lost pitched battle

Pitched battle

A pitched battle is a battle where both sides choose to fight at a chosen location and time and where either side has the option to disengage either before the battle starts, or shortly after the first armed exchanges....

, Knockavoe was in fact the result of a nighttime surprise attack on the O'Neill camp by the O'Donnells.

Background

Conn Bacach O'Neill, Earl of Tyrone

Conn O'Neill, 1st Earl of Tyrone

Conn O'Neill, 1st Earl of Tyrone King of Tír Eógain, c. 1480–1559.-Biography:A son of Conn Mór, King of Tír Eógain, grandson of Henry Ó Néill, the King of Tír Eógain, was the first of the Ó Néills whom the attempts of the English in the 16th century to subjugate Ireland brought to the front as...

, was determined to bring the O'Donnells under his rule and made a great gathering, determined to march into Tyrconnell. Forces arrived from Munster

Munster

Munster is one of the Provinces of Ireland situated in the south of Ireland. In Ancient Ireland, it was one of the fifths ruled by a "king of over-kings" . Following the Norman invasion of Ireland, the ancient kingdoms were shired into a number of counties for administrative and judicial purposes...

 and Connacht

Connacht

Connacht , formerly anglicised as Connaught, is one of the Provinces of Ireland situated in the west of Ireland. In Ancient Ireland, it was one of the fifths ruled by a "king of over-kings" . Following the Norman invasion of Ireland, the ancient kingdoms were shired into a number of counties for...

, together with English contingents, and brought into O'Neill's army itself were the Scoto-Irish MacDonnells of Antrim, Bissetts

Bissett family (Ireland)

The history of the Bissett family in Ireland can be studied independently from that of the originally identical family in Scotland, because of their unique experience following their arrival in Ulster in the early or mid-13th century...

, MacSheehys and others. The forces laid siege to and took Ballyshannon Castle

Ballyshannon Castle

Ballyshannon Castle was a castle at Ballyshannon, County Donegal, Ireland. The castle was a stronghold of the O’Donnell's. No visual remains of the castle exist above ground.-History:...

, and later devastated a large part of Tyrconnell.

Battle

While encamped at Knockavoe, near Strabane

Strabane

Strabane , historically spelt Straban,is a town in west County Tyrone, Northern Ireland. It contains the headquarters of Strabane District Council....

, Conn O'Neill's forces were surprised at night by Hugh Dubh O'Donnell and Manus O'Donnell. Hugh and Manus led their small force quietly up to the campsite and launched a surprise attack before the sentinels were aware of how matters stood, with the two forces fighting furiously in pitch darkness in the midst of the camp. After a long and fearful struggle, in which men found it hard to distinguish friend from foe, the completely unprepared O'Neills and their supporters were routed with a loss of 900 men; and O'Donnell took possession of the camp, with an immense quantity of booty.

Aftermath

The battle was one of the bloodiest ever fought between the O'Donnells and O'Neills, did not end the quarrel. Kildare, who was Conn Bacach O'Neill's first cousin, tried to make peace; but in spite of his efforts the war continued for many years afterwards.

The only long-term result of Knockavoe did not involve the O'Donnells and O'Neills, but rather the MacDonnells and Bissetts. The last Mac Eoin Bissett, Lord of the Glens of Antrim

Glens of Antrim

The Glens of Antrim , known locally as simply The Glens, is a region of County Antrim, Northern Ireland. It comprises nine glens , that radiate from the Antrim Plateau to the coast. The Glens are an area of outstanding natural beauty and are a major tourist attraction in north Antrim...

was slain in the battle, allowing the increasingly strong MacDonnells to seize the lordship from the weakened Bissetts and establish themselves as one of the most prominent families in Ulster.