Led by James Stephens, nineteenth-century Ireland’s most important revolutionary, the IRB rapidly became an increasingly serious threat which Dublin Castle struggled unsuccessfully for years to suppress. In spite of Stephens’s downfall in January 1867 the IRB finally launched a rising and despite its failure, republicans snatched political victory from the jaws of defeat when the execution of the Manchester Martyrs galvanised every shade of Irish nationalism. Rising from the ashes, the IRB survived to eventually become what has been called the most enduring and successful revolutionary secret society in Europe.