Ennis, Sir John (1800–78), 1st baronet, businessman, landowner, and politician, was born 15 August 1800, the only son of Andrew Ennis (d. 1834) of Roebuck, near Dublin, and his wife (née McManus). Andrew Ennis ‘engaged extensively in commercial pursuits and realised a very large fortune’ which enabled him to purchase in 1801 an estate at Griffinstown, Co. Westmeath, and later parts of the Rochfort and Malone estates including the Malone seat at Ballynahown, near Athlone (Burke's peerage). Highly regarded by Daniel O'Connell (qv), he was a trustee of the O'Connell tribute (1830s). John Ennis, after attending school at Stonyhurst, followed his father into business and rose to be governor of the Bank of Ireland (1856–8), only the second catholic to hold this position, and chairman of the Midland Great Western Railway (MGWR) Co. (1847–64). A director of the bank from 1836 until his death, he and Charles Haliday (qv), his successor as chairman, gave evidence to the parliamentary select committee inquiring into the working of the banking acts of 1844–5 (1858). Autocratic and unpopular with the staff of the MGWR (which connected Dublin with the west of Ireland), he did not always conduct the affairs of the company to the satisfaction of its shareholders, who eventually limited his powers (1858) and finally ousted him (26 September 1864). Ennis was a commissioner of charitable donations and bequests (1852–78), and high sheriff of Co. Westmeath (1837) and Co. Dublin (1857). A Liberal, he stood for parliament at Athlone, at first unsuccessfully (1856), then successfully (1857), retaining his seat, partly by exerting patronage, until 1865, when he was defeated by a rival Liberal candidate. He was created a baronet (27 July 1866). He died 8 August 1878 at his Dublin home, 9 Merrion Sq. East. Very wealthy, he owned, in the early 1870s, 8,774 acres in Westmeath and 588 elsewhere and was said to have left a large fortune.
His marriage (in 1834) to Anna Maria, eldest daughter of David Henry (d. 1836), a civil engineer in Dublin, produced a son and three daughters. His daughter Mary married Daniel O'Donoghue (qv), O'Donoghue of the Glens. The son, John James Ennis (1842–84), born 6 April 1842 and educated at Oscott and Christ Church, Oxford (though he did not graduate), seems to have lived off his inheritance. He was high sheriff of County Westmeath (1866) and Liberal MP for Athlone (1868–74 and 1880–84). At the general election of 1874 he and his rival, a home-ruler with clerical support, Edward Sheil, son of Sir Justin Sheil (qv), each got 140 votes; Sheil petitioned and in the subsequent by-election got 153 votes to Ennis's 148. A local catholic bishop, Laurence Gillooly (qv), claimed that Ennis and his father ‘had been for years notoriously engaged, directly and thro’ agents, in corrupting the electors by loans of money’ (quoted in Hoppen, Elections, 63). At the general election of 1880 Ennis, by then the second baronet, standing again as a Liberal, took the seat from Sheil, still a home-ruler, by 163 votes to 162. An active parliamentarian, he took no part in agrarian agitation. Sir John James Ennis died 28 May 1884 of apoplexy at Curzon St., Mayfair, London; he never married.