The nine years war began in 1592. The counties of the north were ablaze with rebellion. For nine years the confederacy of the North resisted England's plan of expansion. Battle after battle the English suffered defeat against a limited Irish army.
Under the strategic mind of O'Neill and the drive and determination of O'Donnell it became one of Irelands most successful rebellions. With Maguire of Fermanagh by their side they would take charge of their territories and beyond. O'Neill was brought up in an English court and was taught the tactics of warfare and the art of diplomacy. Both theses skills he used in abundance.
Ultimately it failed. The power of England was too great and the assistance from the King of Spain was too little, too late. The war ended in 1601 after the defeat of the Irish at the battle of Kinsale, County Cork.