Northern Ireland was created today in 1921, with the partition of Ireland; the South became a dominion.
Since the troubles (guerrilla warfare) began in the late 60s, there has been 50,000 casualties - and 3,500 deaths.
By far, the bloodiest part of the UK - and many residents hope that Brexit will afford it the stability to put the conflicts permanently in the past.
There is a fear though that - if loyalist and/or republican extremists don't get their way - the violence could erupt again.
Yet another dimension of the Brexit saga...