The fall of Charles Stewart Parnell as a result of the O'Shea divorce case in late 1890 is a dramatic episode of lasting human interest and an event of the first importance in the history of Ireland and of British politics. The story of the crisis has often been told, usually from the perspectives of the two Homeric protagonists, Parnell and Gladstone. While it is generally agreed that the English nonconformists played a decisive part in the dethronement of ‘the uncrowned king of Ireland’, their catalytic role has never been clearly, accurately, or fully explained. The problem is of special interest because it was during this controversy that ‘the nonconformist conscience’ entered the English language as a popular phrase as it had long before entered English politics as a potent reality. It is the purpose of this article to study the Parnell affair from the vantage point of English nonconformity and, in so doing, to re-examine the origin of the famous phrase and to throw light on the relationship of nonconformity and the liberal party in a critical phase of the home rule movement.