Myles Byrne was an insurgent leader in Wexford in the Irish Rebellion of 1798 and a fighter in the continued guerrilla struggle against British Crown forces in the Wicklow Hills until 1802. In 1803 collaborated closely with Robert Emmet in plans for a renewed insurrection in Dublin. After these misfired, he took a commission in Napoleon’s Irish Legion, seeing action in the Low Countries, Spain and at the Battle of Leipzig. Under the Bourbon Restoration he was deployed to Greece, and retired as a chef de bataillon. In his later years, he was the Paris correspondent for the Young Irelander paper The Nation, and dictated his memoirs. In these, he advanced the image of the United Irishmen as a cohesive revolutionary organisation dedicated to the achievement of a national democratic government.

The Irish Rebellion of 1798 was a popular insurrection against the British Crown in what was then the separate, but subordinate, Kingdom of Ireland. The main organising force was the Society of United Irishmen. First formed in Belfast by Presbyterians opposed to the landed Anglican establishment, the Society, despairing of reform, sought to secure a republic through a revolutionary union with the country's Catholic majority. The grievances of a rack-rented tenantry drove recruitment.