Following the death of his brother Charles II, James II became King of England, Scotland and Ireland in 1685.

James had one great objective in regard to Ireland and that was to convert it to Roman Catholicism. Roman Catholics benefited, and many obtained considerable estates.
The country exhibited a gloomy scene of oppression and dejection, of insolence and despair, of power exercised without decency and injuries sustained without redress.
Thomas Leland (1722–1785), Irish Anglican priest, historian, translator and academic
The Irish Roman Catholic clergy strongly urged James to conduct a purge of Protestants from the army in Ireland. In letters sent to James, they asked him to
Purge without delay the rest of your Irish Army, increase it and make it wholly Catholic, raise and train a Catholic militia there; place Catholics at the helm of that Kingdom; issue Quo Warrantos against the Corporations in it; put all employs, civil as well as military, into catholic hands…..
“The state of the Protestants of Ireland under the late King James’s government” by William King pp.305-6

watercolour by John Bulfinch
James chose Colonel Richard Talbot (Earl of Tyrconnel) to enact their wishes and he set about this with a vengeance. The policy of turning out 5000 – 6000 Protestant officers began immediately.
These officers and soldiers were replaced by Irish Roman Catholics and by the end of 1687, the remodelling of the army had been completed.
They were marched to some distant place where he thought they were least known, and where they would be put to the greatest hardships. There he stripped them, the foot soldiers of their clothes, for which they had paid, and the troopers of their horses, boots and furniture, bought with their own money, and set them to walk bare-footed one hundred or more miles to their homes or friends. Most of them got no compensation for their horses or arrears of pay.
William King
Fears Justified
The behaviour of this new-raised force left much to be desired. Officers were recruited from the the lowest ranks of the native population and everywhere Roman Catholics were armed, their priests urging everyone to come to Mass armed with a Skean and half pike.
As these new recruits weren’t paid, they were encouraged to raid the houses of Protestants under the pretence of seizing all arms and ammunition and requisition of all horses.
But in reality this became the wholesale plunder of the Protestant population, their houses were broken into, their women assaulted and their property ransacked.
Only 46 years earlier, thousands of protestants were murdered throughout Ulster during the Irish Rebellion of 1641, English writers at the time put the Protestant victims at over 100,000.
The massacre of over 100 people on the bridge at Portadown was one of the bloodiest, with further mass killings across counties Armagh and Tyrone.
The 1641 massacres terrified Protestant settlers who viewed the rebellion as a Catholic conspiracy to massacre all Protestants in Ireland.
Because the majority of the Tyrconnel’s newly commissioned officers were sons and descendants of those who took part in the 1641 rebellion, the fears of a repetition in 1688 were justified.

Heightened Concerns
Tyrconnel meanwhile continued his reforms. Now that the military authority of the State was in the hands of Roman Catholics, he invaded the judiciary, and the civil and corporate rights of the Island.
He transferred the office of Attorney-General from a Protestant to a Roman Catholic, and left only 3 Protestants on the Bench.
Roman Catholic revenue officers displaced Protestants, and Roman Catholic Sheriffs and Justices were appointed all over the Country.
Of the High Sheriffs appointed for 1687 only one was a Protestant, and that was a case of mistaken identity.
In defiance of the law, orders were issued to admit Roman Catholics to membership of the Privy Council and of Corporations without the oaths required by Statute.
Not finding this sufficient, Tyrconnel proceeded to recall civic charters and appoint new Corporations predominantly Roman Catholic. (Corporations were something similiar to town councils with a Mayor, Aldermen, Burgesses and Sherriffs.)
Apart from Londonderry, few towns offered any opposition to these moves.
Rising Tensions
With growing concern and steadily mounting alarm, the inhabitants of the Protestant city of Londonderry witnessed all these developments, deliberately designed to overthrow their religion and encompass their ruin.
And there was plenty of evidence in their own city and neighborhood. The Roman Catholics in the area, seeing how things were developing, looked forward to the day when they would completely dominate the city.
They started to hold Mass daily at the market cross in the city, and the priests started to declare publicly that they had a great design in hand, which would highly concern them and all the nation.
The people were not told what this great design was – it was a top secret. But they were assured that they would have special notices when the time was opportune and that they would have to do whatever their priests should ask of them.
In the meantime they were urged to buy and furnish themselves with the best weapons they could.
Many of the Roman Catholics spoke freely of this, almost in a spirit of boasting, and it became common knowledge among the Protestants of Londonderry and elsewhere.
Throughout the Island, it was observed that not only the men, but women and boys as well were furnishing themselves with skeans and half-pikes, and the Irish smiths all over the country were kept busy making these.

Certain priests in the country secretly warned their Protestant friends to depart because there was a general massacre planned.
In Londonderry, the Roman Catholic soldiers were breaking into houses and forcibly seizing provisions, and had been overheard making threats against Protestants about burning their houses etc.
Departure of Lord Mountjoy’s Regiment
Lord Mountjoy’s Regiment of Foot, had been garrisoned in Londonderry and Culmore for some years. He was a protestant as were a number of his officers, and the regiment was one of the few which had not been entirely purged of Protestants.
The citizens of Londonderry looked upon Mountjoy’s Regiment as a protection against any attack by Roman Catholics. So their anxiety increased when instructions came from Tyrconnel, that the Regiment was to quit Londonderry and march to Dublin.
Their replacement, under the command of the Earl of Antrim, was recruited from Irish and Scottish Highlanders, all Roman Catholics, who soon were nicknamed “Redshanks”.
They were to march to Londonderry and be quartered in the city – fortunately for the residents they were a fortnight late in departing for the city, and so left Londonderry without a Regiment for a period of time.
Unprotected
Whilst the city was left without a garrison, the citizens had time to ponder on all that had happened since James came to the throne 3 years earlier.
The news of the landing of the Prince of Orange on 5th November 1688 was received with a sense of satisfaction by the Protestants of Londonderry, but they felt that the situation was steadily becoming more menacing, and they would not have any help coming immediately.
During several public meetings, Counsellor David Cairnes, a lawyer originally from Co Tyrone, strongly advised the citizens to be prepared for the worst and to form a garrison themselves and watch the gates.
He saw that a number of the younger men of the city including his nephew William Cairnes, were left to carry out his suggestions.
And the discovery of the ‘Comber Letter’ in the first week of December 1688, appeared to prove the wisdom of his advice.
With all of these events, and so closely after the 1641 Massacres, the fears within the Protestant community were understandably high.