Fenians, a political association of Irish or Irish-Americans for the overthrow of the British authority in Ireland, and the establishment of a republic. The name is traced to the ancient Irish military organisation called Fionna Eirinn, said (doubtfully) to have been named from the famous hero of Irish legend, Finn MacCumhail or Fingal (see OSSIAN). This body was designed as a national militia, and its origin has been ascribed to a prehistoric king, who reigned in Ireland about 300 B.C. In time of peace, as was reported, it consisted of three bodies, each formed on the model of a Roman legion, and consisting of 3000 men; but in war it was capable of being enlarged to any required limit. Candidates for enrolment were required to be of an honourable family, to be irreproachable in morals, and to bind themselves to observe the laws of justice and morality; they were required to be of a certain height, and strong, supple, and vigorous of body. The generally historical character of the institution is unquestionable; and it subsisted until the reign of Carby, son of Cormac MacArt, by whom the body of Fionna Eirinn was disbanded; and the members, having in consequence transferred their allegiance to Mocorb, king of Munster, suffered an almost total extermination in the battle of Gavra, 284 A.D. This formed the theme of many a bardic poem from the days of Oisin (known in Gaelic legend as Ossian), son of Finn MacCumhail, downwards.
The modern Fenian movement adopting the name of this ancient military association had its first seat in America, where the Irish population had largely increased since the famine of 1846-47. Many of the emigrants being driven from their homes by arbitrary ejectment, or from inability to pay rent, carried with them a sense of wrong; others had been sympathisers if not participants in the insurrection of 1848; and almost all were deeply imbued with general political and social discontent. The most openly active seat of the organisation was in the western states, especially Chicago; but the movement was directed from New York, and possessed ramifications in almost every city of the Union. It was conducted by a senate, and consisted of 'circles,' each directed by a centre. The duty of the centres was to enrol members, who bound themselves, generally by oath, 'to be faithful to the Irish Republic as at present virtually established;' to instruct and practise them in military exercises; to raise funds for the purposes of the association, especially for the purchase of arms and munitions of war; and to extend the organisation by every means at their disposal. Agents were sent into Ireland, and to the chief seats of the Irish population in England; and, unfortunately, the termination of the civil war in America set free a large number of men with military training and experience. In this, unlike almost all similar movements, pains had been taken to exclude the Catholic clergy, by whom the Fenian confederation had from the first been steadily resisted, from all knowledge of its character and objects, as well as of the names or number of its members in the several localities.
By degrees the movement acquired solidity, and the British government ascertained that Fenianism, however corrupt in some of its sources, and however wild and extravagant in its aims, was nevertheless a reality with which it had become necessary to grapple. The Habeas Corpus Act having been summarily suspended, all the known leaders in Dublin and in the provincial districts of Ireland (most of them Irish-Americans) were at once placed under arrest. The 'Head Centre,' James Stephens, was one of those arrested. The chief journal of the conspiracy, The Irish People, edited by O'Donovan Rossa, was suppressed and seized; additional troops were moved into Ireland, and other measures of repression were vigorously carried out. Many of the prisoners, convicted of treason, were sentenced to penal servitude. By these energetic measures public tranquillity was maintained in Ireland, but the embers of discontent continued to smoulder among the poorer peasantry and the working population of the towns; and a certain prestige was given to the fallen cause by Stephens' escape from prison. His return and that of other exiles to America renewed the agitation in that country. In the early summer of 1866 a raid was attempted into Canada, which proved an utter failure; and it was followed in the spring of 1867 by an utterly abortive attempt at insurrection at home, beginning with the seizure of the castle and military stores at Chester. The attempt was defeated by the treachery of one of the conspirators. A partial insurrection, however, took place in the county of Kerry; and a few weeks later a more extensive movement was attempted in the counties of Dublin, Louth, Tipperary, Limerick, and Cork. But most of the parties dispersed or were made prisoners after a single night's campaign. The rest betook themselves to the mountains, and after a few days of exposure and hardship were either captured or dispersed. The leaders were tried at a special commission held in the spring of the year 1867, some being convicted, but none executed; and tranquillity for a time seemed to be restored in Ireland. In September 1867 an attack was made, in open day, on a police-van in Manchester; the officer in charge was killed, and the prisoners, who were suspected Fenians, were released. A few weeks later a still more daring attempt was made to blow down Clerkenwell Prison wall, with the same object.
In 1871 the United States government frustrated another Fenian raid on Canada by the apprehension of its leaders and the seizure of its arms. Later developments of the Fenian spirit appeared (1883-85) in the Skirmishing Fund, raised to promote the free use of dynamite for the destruction of English public buildings and English commerce, and in the extreme party of the Clan-na-Gael; and some of the 'invincibles' who were to 'make history' by removing tyrants, as in the Phoenix Park assassination (1882), had been Fenians. Some also of those who were leaders in the Home Rule and Land League agitations had formerly been members of the Irish Republican Brotherhood.
See the history of IRELAND in this work; J. Rutherford's Fenian Conspiracy (1877); J. O'Leary's Recollections of Fenians and Fenianism (1896).