The American War of Independence awakened much sympathy in Ulster,
especially among the Presbyterians, who, being disqualified from
holding office, desired a general emancipation including that of
the Roman Catholics.
In 1778 the Irish parliament, under the influence of the reformist
leader Henry Grattan, passed the Relief Act, removing some of the
most oppressive disabilities. Meanwhile Irish Protestants, under
the pretext of defending the country from the French, who had entered
into an alliance with the Americans, had formed military associations
of volunteers, with 80,000 members. Backed by this force they demanded
legislative independence for Ireland, and as a result of Grattan's
tireless campaigning the British parliament repealed Poynings' Law
and much of the anti-Catholic legislation.
Although suffrage was restored to Roman Catholics in 1793, the
Irish parliament remained composed entirely of the Protestants of
the established Church. The principles of the French Revolution
found their most powerful expression in Ireland in the Society of
United Irishmen, led by Wolfe Tone, Napper Tandy, and Lord Edward
Fitzgerald, which instigated the rebellion of 1798.
The peasantry rose in Wexford and, although insufficiently armed,
made a brave fight. At one time Dublin was in danger, but the insurgents
were defeated by the regular forces at Vinegar Hill. A French force
of 1,100 landed in Killala Bay in Mayo but was too late to render
effective assistance. The British prime minister, William Pitt,
the Younger, thought that the legislative union of Great Britain
and Ireland together with Roman Catholic emancipation was the only
remedy for Roman Catholic rebellion and Protestant tyranny in Ireland.
By a lavish use of money and distribution of patronage, he induced
the Irish parliament to pass the Act of Union, and on January 1,
1801, the union was formally proclaimed. Owing to the opposition
of George III, however, Pitt was unable to make good his promise
of emancipation for Roman Catholics.