Between the outbreak of the American Revolution in 1776 and the achievement of free trade in 1780, the eclectic languages of Irish patriotism evolved into an increasingly strident critique of British political control of Ireland. This chapter charts that process while assessing the impact of events in America on Irish political thought. The influence of the American Revolution on Irish patriotism is examined and its ideological importance questioned. This chapter also shows how Irish ancient constitutional traditions gave Irish patriots both a sense of shared ‘English’ inheritance with American patriots as well as a distinctly different understanding of their constitutional position. These ancient constitutional rights were often merged with natural rights. The emergence of commercial grievances as the dominant patriot language between 1776 and 1780 is discussed, along with its fusion with the Commonwealth tradition among radical patriots in the late 1770s.