Cavanagh, Michael (1822–1900), Fenian, poet, and biographer, was probably born 22 January 1822 in Cappoquin, Co. Waterford, the son of Andrew Cavanagh, a cooper of Cook St., Cappoquin, and his wife Mary (née Cullanane). He had six sisters, one of whom, Julia (b. 1833), was the wife of the Cappoquin poet John Walsh (qv). Cavanagh attended the Christian Brothers’ school and John Mulcahy's school in Cappoquin, and afterwards worked as a cooper. He learned Irish from his mother, a native speaker and a schoolfellow of the writer John O'Daly (qv), and she also encouraged his interest in Irish history and local folklore. An uncle inspired a love of Ossianic tales and lays, which Cavanagh learned to recite by heart. Cappoquin was a solidly pro-repeal town and Cavanagh was appointed a repeal warden in the mid 1840s. The agitation for repeal and the sufferings he witnessed during the Great Famine helped to form his nationalist outlook. He supported the Young Irelanders after their secession from the Repeal Association in July 1846 and joined the Cappoquin Confederate Club on its foundation in 1847. Visiting the Swift Confederate Club in Dublin in March 1848, Cavanagh met leading Confederates such as Thomas Francis Meagher (qv), John Mitchel (qv), Thomas Devin Reilly (qv), and Philip Gray (qv).
He was deeply disappointed that the Confederate leadership decided against attempting to rescue Mitchel from Newgate in May 1848 after he was sentenced to fourteen years’ transportation for treason felony. On learning that rebellion had broken out in the south-east, he took the train from Dublin to Tipperary on 25 July 1848 with a pike head (a gift from Mitchel) hidden under his coat. He was given the task of rallying Confederate supporters in Kilkenny and Waterford, but the rising soon collapsed. He blamed the debacle on the lack of preparation and the military inexperience and indecisiveness of the leaders. Unknown to the authorities, he remained in Cappoquin and stayed in contact with Confederates such as James Fintan Lalor (qv), Joseph Brenan (qv), John O'Mahony (qv), John Savage (qv), and Philip Gray, who were trying to reorganise Confederate supporters. On 16 September 1849 their secret organisation attempted to start another insurrection, but could only mount an unsuccessful assault on the police barracks in Cappoquin during which one attacker and a constable were killed. Cavanagh then escaped to America, arriving in New York in January 1850. He worked as a cooper, and by 1852 was living in Shushan in upstate New York, later moving to live with his sister Mary in Waterford, a town on the Hudson; he became a US citizen (15 October 1855).
When the Fenian Brotherhood was founded in the US by John O'Mahony in 1858, Cavanagh, a close friend, acted as his secretary, and was also involved with the related Phoenix Brigade founded in New York, holding the rank of lieutenant. Many members of the Phoenix Brigade joined the fighting in the US civil war in April 1861, but Cavanagh stayed in New York, helping O'Mahony build up the Fenian organisation. He had no quarrel with the South and no wish to fight for the abolition of slavery, but regarded the war as a useful training ground for Irish soldiers and assisted with recruitment to the Irish brigade in autumn 1861. Appointed by the Fenian Brotherhood as a delegate to accompany the remains of T. B. McManus (qv) back to Ireland, he arrived in Dublin in November 1861, and spent the next six months in Ireland, returning to New York on 11 May 1862. In January 1864 the Phoenix Brigade was incorporated into the 99th New York National Guard, and Cavanagh performed garrison duty for some months; there is no evidence that he ever saw action. His writings on the war celebrated the heroism of Irish union troops, but lamented the conflict's ‘fratricidal strife’ and paid generous tribute to Irishmen who served the Confederacy. The courage and resilience of the Irish people in the face of oppression and misfortune is a unifying theme in all his work.
After O'Mahony's resignation from the Fenian Brotherhood in May 1866, Cavanagh's ties with the organisation ended. Leaving New York for Washington DC in spring 1870, he enlisted as a private in the US army and served until 1882 when he was appointed a watchman at the war department with an annual salary of $720. He held this position until his death, and from 1892 was awarded a military pension of $12 a month. The position was not a demanding one, and allowed Cavanagh to concentrate on his writing. Since 1868 he had begun writing for a living in the Emerald, a literary illustrated weekly published in New York. He also contributed to O'Mahony's Irish People. Often he wrote under the pseudonym ‘Cloch an Chúinne’ after a well-known landmark in Cappoquin. He specialised in writing biographies, among them one of his comrade, Joseph Brenan, published in the weekly magazine Young Ireland (20 June–18 July 1885), and, most notably, one of Meagher, serialised in the Worcester Magazine, a catholic monthly (March 1891 to July 1892), and published in book form as Memoirs of Gen. Thomas Francis Meagher (1892). He also published his own verse and translations from Irish in the Irish American and the Emerald, and was a regular contributor to the Celtic Monthly and the Boston Pilot.
Cavanagh translated some of Douglas Hyde's (qv) poems into English, and Hyde praised the results. He was also a friend of Fr Michael O'Hickey (qv) who maintained that Cavanagh knew more of the history, folkore, and topography of Waterford than anyone else he had ever met. When the Ancient Order of Hibernians in 1895 proposed and funded a chair of Irish at the Catholic University of America, Washington DC, Cavanagh, a leading member of the organisation, successfully recommended Fr Richard Henebry (qv) to O'Hickey for the post.
Badly injured by a fall down the stairs two days earlier, Cavanagh died 21 June 1900 in Washington. He was buried in the family plot in Mount Olivet cemetery. On 25 July 1863 in Brooklyn he married Anne O'Brien (1844–1918), a native of Affane, Co. Waterford; they had nine children.