This article examines William Sharman Crawford’s participation in mid-nineteenth-century popular radicalism in England. Despite his unusual background as a wealthy Irish landlord and his limitations as a politician, Sharman Crawford emerged as an important figure in Chartism, especially during the early 1840s when he served as MP for Rochdale. His support from across Chartism resulted from his principled positions, particularly on suffrage, that demonstrated a commitment to democracy pursued through constitutional means. He emphasized the unjust nature of the exclusive legislation that resulted from an inadequate franchise and framed Chartist reforms as echoing past efforts in England and Ireland. Drawing on archival materials and the newspaper press, this article argues for Sharman Crawford’s significance in bridging the divides of radicalism in this era.