Members of the Protestant Dissenter tradition (mainly Presbyterian) make common cause with Roman Catholics in a republican rebellion inspired and led by the Society of United Irishmen in 1798,  with the aim of creating an independent Ireland.

Despite assistance from France the rebellion is put down by British and Irish government and yeomanry forces.

In 1800, the British and Irish parliaments both pass Acts of Union that, with effect from January 1, 1801, merge the Kingdom of Ireland and the Kingdom of Great Britain to create a United Kingdom of Great Britain and Ireland.

The passage of the Act in the Irish Parliament is ultimately achieved with substantial majorities, having failed on the first attempt in 1799.

According to contemporary documents and historical analysis, this was achieved through a considerable degree of bribery, with funding provided by the British Secret Service Office, and the awarding of peerages, places and honors to secure votes.

Thus, the parliament in Ireland is abolished and replaced by a united parliament at Westminster in London, though resistance remains, as evidenced by Robert Emmet's failed Irish Rebellion of 1803.

Irish republicans and nationalists, known as the Society of United Irishmen, launch a rebellion against British rule, in expectation of greater support from France, which only sends eleven hundred men.

The United Irishmen are unique among Irish nationalist movements, in that they unify Catholics and Protestants around republican ideals.

The rebellion rages sporadically, but is defeated by the British by October.

British troops quickly and brutally suppress the brief and violent Irish Rising of 1798.

Loyalists across Ireland have organized in support of the Government; many supply recruits and vital local intelligence through the foundation of the Orange Order in 1795.

The Government's founding of Maynooth College in the same year, and the French conquest of Rome earlier in 1798, both help secure the opposition of the Roman Catholic Church to rebellion; with a few individual exceptions, the Church is firmly on the side of the Crown throughout the entire period of turmoil.

In March 1798, intelligence from informants among the United Irish cause the Government to sweep up most of their leadership in raids in Dublin.

Martial law is imposed over most of the country and its unrelenting brutality puts the United Irish organization under severe pressure to act before it is too late.

A rising in Cahir, County Tipperary, breaks out in response, but is quickly crushed by the High Sherrif, Colonel Thomas Judkin-Fitzgerald.

Militants led by Samuel Neilson and Lord Edward FitzGerald dominate the rump United Irish leadership and plan to rise without French aid, fixing the date for May 23.

The planned nucleus of the rebellion has imploded, but the surrounding districts of Dublin rise as planned and are swiftly followed by most of the counties surrounding Dublin.

The first clashes of the rebellion take place just after dawn on May 24.

Fighting quickly spreads throughout Leinster, with the heaviest fighting taking place in County Kildare where, despite the Government's successfully beating off almost every rebel attack, the rebels gains control of much of the county as military forces in Kildare are ordered to withdraw to Naas for fear of their isolation and destruction as at Prosperous.

However, rebel defeats at Carlow and the hill of Tara, County Meath, effectively end the rebellion in those counties.

News of the rising spreads panic and fear among loyalists in County Wicklow; they respond by massacring rebel suspects held in custody at Dunlavin Green and in Carnew.

A baronet, Sir Edward Crosbie, is found guilty of leading the rebellion in Carlow and executed for treason.

Anthony Perry, born in County Down, Ireland to a Protestant family, has lived a prosperous life at Inch near the Wexford/Wicklow border as a gentleman farmer.

He had enlisted in the local yeomanry corps as a second lieutenant responding to the Governments appeal to save the kingdom from radicalism during the height of anti-Jacobin paranoia in the mid-1790s.

However, the atrocities he had witnessed, and may even have participated in, had disturbed him so much that he had taken the United Irish Oath in 1797 and had been made a colonel.

As a United Irish colonel, Perry is responsible for the organization and recruitment of the movement in north Wexford.

A measure of this success is evident by the fact that the brutal coercion campaign unleashed by the Government 1797-98 does not identify Wexford as a United Irish stronghold until barely a month before the eventual outbreak.

The arrival of the counterinsurgency campaign in Wexford, embodied by the dispatch of the dreaded North Cork Militia, ensures that high profile radicals like Perry will be the first to be subjected to arrest and interrogation.

On May 23, Perry is arrested and taken by the North Cork Militia to Gorey for interrogation.

After enduring 48 hours of torture including being pitchcapped, Perry breaks and reveals some names of comrades in the south Wexford movement but little of the north Wexford organization.

Acting upon the information tortured out of him, the authorities releas Perry on May 26 and concentrate mainly on a roundup of the United Irish leaders in Wexford town.

While the authorities concentrate on extracting intelligence about the rebel organization from southern leaders such as Bagenal Harvey, Edward Fitzgerald, and John Henry Colclough, the rebellion erupts rapidly after being sparked off by a clash at The Harrow where rebels under Fr.

John Murphy attack and defeat a small yeoman cavalry force.

A bloody series of raids for arms and attacks on loyalist forces ensues across the northern half of the county, countered by roaming bands of yeomen burning and killing indiscriminately.

Victories at battle of Oulart Hill and Enniscorthy follow, leaving the rebels in total control of the area between Enniscorthy and Gorey by May 29.

Despite his horrific wounds, Perry reports to the rebel camp at Vinegar Hill, Enniscorthy on 29 May and is appointed as second in command to the northern army.

The initial plan is to take Dublin, with the counties bordering Dublin to rise in support and prevent the arrival of reinforcements followed by the rest of the country who were to tie down other garrisons.

The signal to rise is to be spread by the interception of the mail coaches from Dublin.

However, last-minute intelligence from informants provides the Government with details of rebel assembly points in Dublin and a huge force of military occupies them barely one hour before rebels are to assemble.

Deterred by the military, the gathering groups of rebels quickly disperse, abandoning the intended rallying points, and dumping their weapons in the surrounding lanes.

In addition, the plan to intercept the mail coaches miscarries, with only the Munster-bound coach halted at Johnstown, near Naas, on the first night.

The intimate nature of the conflict means that the rebellion at times takes on the worst characteristics of a civil war, especially in Leinster.

Sectarian resentment is fueled by the remaining Penal Laws still in force and by the ruthless campaign of repression prior to the rising.

Rumors of planned massacres by both sides are common in the days before the rising and lead to a widespread climate of fear.

Atrocities will be committed by both sides during the rebellion.

The aftermath of almost every British victory in the rising is marked by the massacre of captured and wounded rebels with some on a large scale such as at Carlow, New Ross, Ballinamuck and Killala.

The British are responsible for particularly gruesome massacres at Gibbet Rath, New Ross and Enniscorthy, burning rebels alive in the latter two.

For those rebels who ae taken alive in the aftermath of battle, being regarded as traitors to the Crown, they are not treated as prisoners of war but are executed, usually by hanging.

The British establishment recognizes sectarianism as a divisive tool to employ against the Protestant United Irishmen in Ulster; the divide-and-conquer method of colonial dominion is officially encouraged by the Government.

Brigadier-General C.E. Knox writes to General Lake (who is responsible for Ulster): "I have arranged... to increase the animosity between the Orangemen and the United Irishmen, or liberty men as they call themselves. Upon that animosity depends the safety of the centre counties of the North." (Lecky, William Edward Hartpole. A History of England in the Eighteenth Century, Volume VII. D. Appleton And Company, New York, 1890, p. 312.)

Similarly, the Lord Chancellor of Ireland, John FitzGibbon, writes to the Privy Council in June 1798, "In the North nothing will keep the rebels quiet but the conviction that where treason has broken out the rebellion is merely popish", expressing the hope that the Presbyterian republicans might not rise if they think that rebellion is supported only by Catholics. (Letter to Privy Council, 4 June 1798 "A Volley of Execrations: the letters and papers of John Fitzgibbon, earl of Clare, 1772–1802", edited by D.A. Fleming and A.P.W. Malcomson. (2004))

Mostly Presbyterian rebels led by Henry Joy McCracken rise in the northeast on June 6 in County Antrim.

They briefly hold most of the county, but the rising there collapses following defeat at Antrim town.