Donnelly, Nicholas (1837–1920), catholic bishop, church musician, and local historian, was born 23 November 1837, in St Paul's parish, Dublin, eldest son of John Donnelly, a merchant. He was educated at Castleknock College and the Irish College, Rome, where he was ordained priest 1 November 1860. His first appointment as a curate was to St Nicholas's, Francis St., Dublin in 1861, where his parish priest was Edward McCabe (qv). He was moved to the pro-cathedral, Marlborough St., in 1864, promoted administrator (equivalent to parish priest) of St Andrew's, Westland Row, in 1879, then parish priest of Rathgar in 1882, Bray, Co. Wicklow, in 1894, and eventually back to Dublin as parish priest of Haddington Road and dean of Dublin in 1904. While at Rathgar he was appointed titular bishop of Canea and auxiliary to Archbishop McCabe on 3 October 1883. But when, after McCabe's death, the Dublin diocesan clergy voted on a successor on 10 March 1885, he got only twelve votes while William Joseph Walsh (qv), the abler candidate, got forty-six. In his politics Donnelly was out of sympathy with the agrarian agitation of the 1880s. His great passion was church music and ritual. During his curacy at the pro-cathedral a new organ was installed (1869–70), which he regularly played. His English translation of F. X. Haberl's Magister choralis (1877), directed and revised by the author, was complemented by the first number of Lyra Ecclesiastica (1879), which Donnelly edited, describing it as the ‘monthly bulletin of the Irish Society of St Cecilia’.
His dedication to Gregorian music was shared by Walsh, author of Grammar of Gregorian music (1885) and, like Donnelly, a forerunner of Heinrich Bewerunge (qv). Donnelly was a founder member and a vice-president of the RIAM. He is best remembered for his modestly titled but extensive A short history of some Dublin parishes (1905–17), published in a series of fascicules by the Catholic Truth Society of Ireland, of which he was a founder member. He contributed articles on music and local history to newspapers and magazines. Donnelly was fond of travel, particularly in Italy, spoke Italian and French well, and had excellent discourse. As a parochial and diocesan administrator he was energetic and effective. He was elected a member of the RIA (1885), a rare distinction for a catholic bishop, and was vice-president (1893–8, 1899–1905). He died 28 March 1920 and his funeral was fittingly elaborate. A portrait of Donnelly holding the plans of the church of Our Most Holy Redeemer, Bray, built by him when parish priest, hangs in the sacristy of that church beside paintings of Walsh and Leo XIII; all three were painted by a Neapolitan artist, Eduardo Buccini, commissioned by him.