Short answers, pulled from the story.
Northern Ireland officially came into existence on the 3rd of May 1921 when the Government of Ireland Act 1920 took effect. This legislation divided the island of Ireland into two self-governing territories within the United Kingdom.
The thirty-year period of intense sectarian violence known as The Troubles lasted from 1969 to 1998 and claimed over 3,500 lives while injuring 50,000 others. Armed campaigns began early in 1969 when the Provisional IRA targeted British rule and continued until paramilitary organizations declared ceasefires under international supervision.
Michelle O'Neill assumed office as deputy First Minister on the 3rd of February 2024 becoming the first ever Irish nationalist Catholic or republican to hold that position. She had not taken up her role earlier because the Democratic Unionist Party refused to nominate a deputy First Minister until new legislation passed.
Northern Ireland comprises six northeastern counties including Antrim Down Armagh Londonderry Tyrone and Fermanagh. These areas formed the new entity with a Protestant majority population who desired to remain part of Britain.
Lough Neagh stands as the centrepiece of Northern Ireland's geography being the largest freshwater lake on the island of Ireland. Volcanic activity created the surrounding Antrim Plateau which also formed geometric pillars known as the Giant's Causeway along the north Antrim coast.