(The). An Irish Fenian organisation founded in Philadelphia in 1870, and known in secret as the “United Brotherhood”; its avowed object being to secure “the complete and absolute independence of Ireland from Great Britain, and the complete severance of all political connection between the two countries, to be effected by unceasing preparation for armed insurrection in Ireland.” (See Dynamite Saturday .)
In 1883 Alexander Sullivan was elected one of the three heads of this club, to which is due the dynamite
outrages in London (January, 1885), and the design to murder the Queen's ministers.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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