This article reconstructs the underexamined stage history and reception of one of the most popular stammering figures of the nineteenth century: the bumbling aristocrat Lord Dundreary, as performed by E. A. Sothern. Dundreary originated in Tom Taylor’s comic melodrama Our American Cousin, which premiered in 1858 and is best remembered today as the backdrop of Abraham Lincoln’s assassination. Sothern rewrote and expanded the originally minor part and received acclaim for his portrayal on both sides of the Atlantic for several decades. This praise centred on Sothern’s performative blend of stammering and lisping speech used to animate Dundreary and amuse audiences. Dundreary’s unprecedented dysfluent stardom is situated within the context of nineteenth-century vocal discourse’s frequent hostility to modes of speech that deviate from social norms of fluency, pace and articulacy. In particular, the theatrical culture from which Dundreary emerged construed a dysfluent actor as a liability while celebrating a dysfluent character, illuminating an evaluative schism between innate and performed vocal disability. Prescient of contemporary vocal hierarchies, Dundreary’s reception demonstrates that entertainment value mitigates the stigma that otherwise accrues to dysfluent voices. Dundreary obtains cultural centrality as a dysfluent speaker on stage in a manner foreclosed to dysfluent speakers offstage.