Fitzgerald, William Robert (1749–1804), 2nd duke of Leinster , Volunteer colonel, was born 13 March 1749 in Arlington Place, Piccadilly, London, the second son of nine sons and ten daughters of James Fitzgerald (qv), 20th earl of Kildare and later 1st duke of Leinster, and his wife, Lady Emily Lennox (qv). Educated at Eton (1758–63), he embarked on the grand tour and at the age of eighteen became a freemason in Naples. In 1765, on the death of his elder brother, he became heir apparent to his father, with the courtesy title of earl of Offaly. The following year his father was created duke of Leinster (the only dukedom in the country) and Fitzgerald in turn became marquess of Kildare.
He was returned as MP for Dublin city in 1767, though he was too young to take his seat, and it was only in October 1769 that he returned to Ireland to sit in parliament. He represented the constituency until 1773, supporting the government for most of this period. On learning that he was a freemason, the grand lodge of Irish freemasons rushed to make him their grand master and he served two terms (1770–72 and 1777–8). On 19 November 1773 he succeeded his father as 2nd duke of Leinster. The family home of Carton in Co. Kildare had been left to his mother but he, somewhat vainly, was determined to own it and purchased her life interest, a transaction that was the major source of his future indebtedness. His aunt, Lady Louisa Conolly (qv), believed that he was ‘mighty queer about money’ and that his ‘distress’ about it was ‘the foundation of all that he does’ (HIP, iv, 160). In November 1775 he married Emilia Olivia Usher, only daughter and heir of St George Usher, Lord St George, a union that helped to ease some of his financial problems.
Determined to be recognised and accepted as a leading figure in Ireland, he wrote to the viceroy, Lord Harcourt (qv), in March 1774 telling him that he expected ‘to be informed of intended measures’ (HIP, iv, 160). In the autumn of 1778 the first Volunteer company was established in Dublin, and Fitzgerald was chosen as its colonel because of his popularity and prestige. He was a dominant figure during the campaign for free trade in 1779, but his moderation on the issue of legislative independence led to his replacement by Lord Charlemont (qv). He was a regular supporter of the whig opposition, except for occasional defections to the government ranks, for example in 1780–84, when as a reward he was made KP in 1783. In 1782 he brought William Ogilvie (qv), his mother's second husband, into parliament for one of his boroughs.
In 1788 he was appointed master of the rolls and now seemed permanently reconciled with the government. However, during the regency crisis of 1788–9 he decided to throw his support behind the opposition in the expectation that once the prince of Wales was regent the ministry would be changed in Britain. The recovery of George III, however, shattered his ambitions and he was one of the ‘rats’ punished by the government, with many dismissed or threatened with loss of office; this prompted him to return to his position as the symbolic leader of the opposition in the lords. He was involved in the formation of the new whig clubs in Ireland in 1789, alongside Henry Grattan (qv). He supported catholic relief, but in 1792, when he felt he had overcommitted himself in favour of emancipation, he used an address from Athy corporation as an excuse to disengage honourably. He subsequently voted against the two relief measures brought forward. His financial difficulties continued throughout the 1790s, and he was obliged to sell some of his borough patronage; as a result, his political influence in Co. Kildare began to wane.
He briefly supported the government again in 1795–6. In March 1798 a warrant was issued for the arrest of his younger brother Lord Edward FitzGerald (qv) for treason. Lord Edward was apprehended in May and died shortly afterwards from wounds he had received during his capture. When his brother Lord Henry Fitzgerald (qv) visited him in prison, Edward spoke highly of his eldest brother, ‘for whom I have a high respect. He might depend on everything I did’ (Tillyard, Aristocrats, 390). During this period Leinster was often in tears, distraught at Edward's condition and also the health of his wife, who was suffering from a terminal illness. Despite this, the first debate on the Irish rebellion in the house of lords, on 15 June, was on his motion. His wife died 23 June 1798 at Thomas's Hotel, Berkeley Square, London.
After the Act of Union, Leinster allowed his brother Lord Robert Stephen Fitzgerald (1765–1833) to stand for election in Kildare, even though he was a supporter of William Pitt. Lord Robert was elected in 1802, thus protecting the family dominance in the county, which had been under threat.
Somewhat pompous, Leinster laboured against the persistent feeling that he was a disappointment; even his mother once said that he was ‘très médiocre’ (Tillyard, Aristocrats, 344). Nevertheless, he was an important figure politically, more because of the prestige of his position and his popularity than his (limited) abilities.
Leinster had three sons and six daughters. He died of strangury, a urinary tract disorder, at Carton on 20 October 1804 and was buried in Kildare Abbey. His funeral was so well attended that the mourners reached across the Curragh. He was succeeded by his second, but eldest surviving, son, Augustus Frederick Fitzgerald (qv), as 3rd duke of Leinster.