'The Twelfth Week' refers to the week's holiday in July which all manual workers in Northern Ireland get to enable them to celebrate, or escape from, the celebrations of 12 July.
The Battle of the Boyne
On 12 July, 1690, the forces of the British Catholic King James II met the forces of the Dutch Protestant King William of Orange1 at the River Boyne in Ireland. James had already been deposed from the English throne in 1688 and landed in Ireland in 1689 with French troops. The Irish Protestants, along with their English allies, wanted William (who was married to James' sister Mary) to become their King and re-establish Protestantism as the state religion.
James had earlier been locked out of the city of Londonderry by the Apprentice Boys. He was far from being a popular King. However the battle unfolded and William's forces were victorious. The Treaty of Limerick in 1691 effectively ended the war.
Celebrating the Battle
The Loyal Orange Order was set up by the Protestant community in Ireland to celebrate that day of the Battle of the Boyne. They would march through their towns as a memory of what was achieved on that day. This celebration has turned into a great divide in the community. And the likes of Drumcree2 and other marches are no longer allowed to freely follow the traditional routes they once followed because of shifting populations changing the religious affiliations of the area.
Every 12 July a historical re-enactment of the Battle of the Boyne takes place at Scarva. The two sides these days wear green and orange rather than the battle-dress the real armies would have worn on the field. It looks more like a football match at times. The fight moves are carefully orchestrated and unlike many historical re-enactments in the rest of the UK, this sham fight is mainly a social points scoring exercise rather than an accurate portrayal.