Fitzgerald, William Vesey (1783–1843), politician and chancellor of the Irish exchequer, was the second, but eldest surviving, son of James Fitzgerald (qv), prime serjeant, and Catherine Fitzgerald (née Vesey). Educated at Christ Church, Oxford, he became in 1808 MP for Ennis, Co. Clare, taking his father's seat. Notoriety soon followed, as in 1809 he was involved in the scandals surrounding Mary Anne Clarke, mistress of the duke of York, which threatened to wreck his career. The sordid nature of the affair, and his father's involvement, gave it national prominence, but William emerged relatively unscathed after he provided evidence for the government against Clarke, and in February 1810 he was appointed a lord of the Irish treasury, and an Irish privy councillor. In 1812 he was appointed chancellor of the Irish exchequer (until 1816), and lord of the treasury (until 1817). The controversy returned in 1813 when Clarke wrote a public letter to him which contained a scathing attack on both father and son. It was claimed that he had a serious gambling problem, and had seduced the wife of his best friend, before forcing the woman to miscarry after she became pregnant. Few were willing to believe these allegations, and his reputation was not seriously damaged; Clarke was imprisoned for nine months for libel.
On 13 February 1815 William and his brother, Henry, took the name Vescy, by royal sign manual, to go before Fitzgerald. He normally spelt it Vesey, although on some promotions his title was spelt Vesci. A respected and trusted politician, he was a friend of Robert Peel (qv), but Lord Liverpool, prime minister 1812–27, believed that he lacked ‘judgement and temper’. He was elected MP for Co. Clare (1818–28) and appointed envoy to the court of Sweden (1820–23). Benefiting from Peel's patronage, he was appointed paymaster of the forces (1826–8), and in 1828 president of the board of control, necessitating his seeking reelection. This proved the catalyst for one of the most dramatic and important elections in Irish history. The Catholic Association was determined to oppose any supporter of the ministry, even though Vesey Fitzgerald was a supporter of catholic rights and a popular figure in the county. The election took an important turn on 24 June, less than two weeks before polling, when Daniel O'Connell (qv) decided to stand, giving the contest a far-reaching significance. Only one parish priest supported Fitzgerald, and the groundswell of popular and clerical support for O'Connell decided the issue. On nomination day Fitzgerald resorted to his usual ploy of emotionalism, bursting into tears as he spoke of his dying father, and drawing a stern rebuke from O'Connell, who is however recorded as lapsing into what Oliver MacDonagh calls ‘proto-Kiltartanese’: ‘Arrah, bhoys, where's Vasy Vijarld at all, at all? . . . sind the bell about for him. Here's the cry for yez: Stholen or sthrayed. Losht or mishlaid, The President of the Boord of Thrade!’ (MacDonagh, 253). At the end of the third day of polling Fitzgerald trailed by 982 votes to 2,057 and failed to be elected.
Given a government seat at Newport in the aftermath, in 1830 he became MP for Lostwithiel. He was elected for Ennis in 1831. He succeeded to his mother's peerage on her death in 1832. On 10 January 1835 he was created Baron Fitzgerald of Desmond and Clan Gibbon of Co. Cork. He was appointed president of the board of control in 1841, although he was an invalid in the last few years of his life.
He died 11 May 1843 in London, and was buried at Kensal Green cemetery. He was unmarried, and the barony of Desmond and Clan Gibbon became extinct. His brother, Henry, succeeded him as Baron Fitzgerald and Vesey . His will left the remainder of his estate to his two illegitimate children, one of whom, Sir William Robert Seymour Vesey Fitzgerald, became an MP and governor of Bombay.