For centuries, the English maintained rule in Ireland. The two had been joined politically after the Norman invasion of Ireland in 1169 and 1171 under Henry II with permission of Pope Adrian IV (the only English Pope in Catholic history) to aid Dermot MacMurrough in retaking his lost throne in Leinster. Henry made further conquests in Dublin and created the Lordship of Ireland, making much of the island vassal states with relative independence. Henry VIII, as part of his Protestantizing of England, was named King of Ireland to assure his political dominance over the vast Catholic majority. When Ireland supported the Catholic James II against the incoming Protestant Mary and her husband, William of Orange, and lost the Williamite War in 1691, rule became systematized through the Ascendancy, the Protestant minority who controlled the Church of Ireland.
In 1791, the Society of United Irishmen was founded in Belfast by liberal-minded Protestants who sought togetherness through Irish nationalism and an end to religious divisiveness. The success of the revolution in France excited the Irish in Ulster to find unity, which was a stark difference to the typical thinking that inspired sectarian warfare such as that between the Protestant Peep o' Day Boys and the Catholic Defenders. Loyalists fanned the flames of violence between them and contributed to founding the Orange Order as another society to counterbalance the efforts of the United Irishmen. When it became obvious that the goal of universal suffrage was not to be found politically, the United Irishmen looked for help in 1794 from revolutionary France, who dispatched an army of 14,000 soldiers in 1796 that never landed due to inclement weather and poor leadership. Uprising continued in Ireland without them, and the British reacted with violent measures such as execution, arson, torture, and pitchcapping. Martial law spread over much of the island, and loyalist spies among the rebels led to the capture of much of the Irish leadership.
On the night of May 23, the British military received late notice of an Irish march on Dublin. Samuel Neilson and Lord Edward FitzGerald, two of the remaining Irish leadership, decided to capitalize on the unrest born from martial law. British soldiers marched en masse to capture rebel meeting places, but they found them already held by the Irish. In furious firefights throughout the city's alleys and squares, the cunning and local knowledge of the rebels won out over superior British firepower. The city fell along with hundreds of British dead and thousands captured. Rebels intercepted mail-carriages, which was the secret signal to alert their allies in the surrounding counties.
While the British stopped a similar uprising at Carlow, the rebellion won out at Tara Hill and spread to the north, where it turned into guerrilla warfare among those seeking independence and those loyalists and Catholics who had come to distrust revolution after the French's capture of Rome three months before. Wexford (where the Normans had come into Ireland some 600 years before) became the center of Irish success, and the rest of the island became embroiled in war. In September, France finally made good on its promise of support, sending thousands of troops by sea into County Mayo on the northwest, giving all but Ulster to the revolution. The British, now wary of French intervention, began a blockade of the island, and a second expedition in October was intercepted. While the French were scattered, a few made it to shore, including Theobald Wolfe Tone, one of the original leaders of the United Irishmen who had been in exile since 1793 after the first discovery of communications with the French.
Wolfe soared through the ranks of the Irish with great promises, using to his advantage his theatrical leanings and firsthand knowledge of the French Revolution as well as interviews with General Napoleon (who himself did not much believe in the success of an Irish movement). Among some of his first actions were to remove the strength the Anglican Church, and then to weaken the Catholic church, placing as much property and money into government hands loyal to him. Wolfe dispatched Robert Emmet to the newly crowned Emperor Napoleon for additional aid, which was supplied, though the British redoubled their efforts to find a foothold among loyalists frustrated with Wolfe's rule. Napoleon was dubbed the greater enemy, however, and the fighting in Ireland grew into a stalemate until 1812 with Allied success in the Peninsular War and Napoleon's disastrous invasion of Russia.
After forced abdication in France, the British turned on Ireland, where Wolfe was hastily overthrown. The chaos continued until the newly made Duke of Wellington, Arthur Wellesley, an Irishman, was made military governor. While he was very popular in London because of his war service, he became immensely popular in Ireland after championing reforms, particularly Catholic Emancipation. With a better balance of political rule, reinforced by groundbreaking social services instituted during the Great Famine of the 1840s. Wellington's liberal nature, applauded by the Tories, would prove too much for British sensibilities, hamstringing his chances of a prime ministership.
Since its turbulent, short-lived republic, Ireland has been a key member of the British Commonwealth. It aided greatly in many of the Empire's international concerns including both world wars, although a renewed independence movement out of the Lost Generation in the 1920s that came mainly as social reforms and literary marvels.
In reality, the capture of Dublin was foiled. While gains were made in Wexford over the summer of 1798, Britain put down the rebellion, albeit with substantial violence. Ireland would go through further rebellions in 1803, 1848, 1867, and 1913 until finally winning its independence in 1921. Ulster remained with the United Kingdom and would be the site of additional violence through the 1990s.