Blacker, William (1777–1855), militia officer and Orangeman, was born 1 September 1777 at Carrickblacker, near Portadown, Co. Armagh, first of four sons of Stewart Blacker (1740–1826), dean of Leighlin and owner of Carrickblacker, and his wife Eliza, daughter of Sir Hugh Hill (1728–95), baronet, for many years MP for Londonderry city. After an education at Armagh Royal School, he entered TCD (5 October 1795). Only two weeks earlier in Co. Armagh he had carried ammunition to the Peep o’ Day Boys at Loughgall engaged in a victorious fight with Defenders, which became known as the ‘battle of the Diamond’ and gave rise to the first Orange society. By his own account, he joined straightaway and was thus the first member of the gentry to join the Orange movement. While a student at Trinity College he formed an Orange lodge at Carrickblacker (‘No. 12’), took a leading part in the first Orange parade at Lurgan (12 July 1796), helped to form a college lodge, and became the first grand master of Co. Armagh (1797); he was a delegate at the meeting held in Dublin on 8 March 1798 to form the Orange grand lodge of Ireland.
Blacker was appointed (30 October 1796) a captain in the Seagoe yeomanry (infantry), and in October 1797 joined the college yeomanry (3rd company). During the rebellion of 1798 he was on guard duty in Dublin. In 1798 also he was summoned to Dublin castle and asked by the chief secretary, Lord Castlereagh (qv), to form a yeomanry corps made up of Orangemen; when he agreed he was sent north ‘with an order for 100 stand of arms’. On 3 July 1801, two years after taking his degree, he obtained an ensigncy in the 60th regiment, then serving in the West Indies, but when his health failed he returned home. He then raised a company in the Armagh regiment of militia, holding the rank of lieutenant colonel from 1812 until its disbandment in 1816. During the 1820s he still headed a yeomanry corps.
In 1811 Blacker was high sheriff of Co. Armagh. In January 1817 he was appointed, through the influence of his uncle, Sir George Hill (qv), to be deputy treasurer for Ireland. Based in Dublin, he held office until 1829, when he resigned in order to devote his time to the Carrickblacker estate, which he inherited on the death of his father (1 December 1826). He declined to join the Brunswick clubs, formed in August 1828 after the suppression of the Orange grand lodge of Ireland under the Unlawful Societies Act (9 March 1825), but was prominent again in Orange circles after the act's lapse in 1828. When in 1833, after the passing of the Party Processions Act (16 August 1832), Portadown Orangemen demonstrated on the Carrickblacker demesne, Blacker as a magistrate advised them to disperse but had the ladies of his household display Orange lilies. For this he was deprived of his commission of the peace on the advice of Lord Gosford (qv), the whig governor of the county. In 1835 Blacker gave evidence to the parliamentary inquiry into Orangeism; his testimony occupies thirty-seven pages of the report. When on 14 April 1836 the grand lodge of Ireland recommended its own dissolution he demurred.
Blacker was also a poet, later praised by D. J. O'Donoghue (qv). He wrote many Orange ballads, among them ‘The battle of the Boyne: an historical ballad’, ‘The Diamond will be trumps again’, ‘No surrender’, and ‘Oliver's advice’ (others are in the Blacker MSS at the Armagh County Museum). Anonymously he contributed prose as well as verse to periodicals and published four volumes of verse: Ardmagh: a chronicle (1848), Early piety (1853), A tale of woe for children (1854), and Emmaus: a tale for Easter (1855). His reminiscences (written c.1837), extracts of which were published by Constantia Maxwell (qv), record his student career at TCD and his opposition to rebellion as well as illuminating the visits to Dublin of George IV and Sir Walter Scott.
William Blacker married (November 1810) Anna, daughter of Sir Andrew Ferguson (1761–1808), baronet, MP for Londonderry city (1798–1800). He died 25 November 1855 at Carrickblacker. As there were no children of the marriage, Blacker's property passed to his nephew Major Stewart Blacker (d. 1881), barrister, MRIA, high sheriff of Co. Armagh (1858–9), and for many years secretary of the Orange grand lodge of Ireland. Lieutenant-colonel William Blacker, who ‘combined the highest of Tory principles with literary tastes’ (Greene), was a distant relative of William Blacker (qv) (1776–1850), the land agent.