In Northern Ireland, 2001 will primarily be remembered as the year in which the IRA, following years of refusals, finally took the giant step of decommissioning some of its weaponry.
Although some elements were dismissive of the event, the British and Irish governments remain convinced that it was a watershed in the peace process and the strongest of signs that the IRA will not go back to war.
Decommissioning took place in October, after a year in which the political system was racked with recurring crises. Talks aimed at breaking the log-jam on the issues of weapons, policing and demilitarisation failed to produce a breakthrough in the first half of the year.
In the June election the more centrist parties did badly while those on the extreme, Sinn Fein and the Paisleyite Democratic Unionists, made significant gains, reflecting a polarised electorate.
In July, the Unionist leader David Trimble resigned as First Minister of the fledgling power-sharing executive, which led to yet more talks as meltdown threatened the peace process.
Talks deadlines were repeatedly extended while the Government made what were widely regarded as being a series of concessions to Sinn Fein. Eventually, with the devolved government apparently on the point of disintegration, the IRA decommissioned.
The political excitements continued, however, as Mr Trimble only narrowly squeaked through on a vote to reinstate him as First Minister. Political ill feeling erupted afterwards when Assembly members clashed in ugly scenes in Stormont in what came to be known as "the brawl in the hall".
Scenes on the streets were even uglier, where 19 people were killed during the year. Fourteen of these were the work of loyalist extremists as two Protestant groups abandoned their ceasefires, while the Real IRA remained active, staging several bomb attacks in London.
One notable victim of loyalists was Martin O'Hagan, who became the first journalist to die in the Troubles.
North Belfast in particular saw widespread violence as crowds of both loyalists and republicans clashed with each other and with the security forces. The ugliest sights of all took place at Ardoyne where for months loyalists staged protests aimed at preventing Catholic children going to the Holy Cross primary school.
Important changes in policing took place during the year, the Royal Ulster Constabulary becoming the Police Service of Northern Ireland. The sense of a new start was marred during December, however, when sharp controversy erupted over the 1998 Omagh bomb.
Chief Constable Sir Ronnie Flanagan publicly clashed with Police Ombudsman Nuala O'Loan over possible warnings about the bombing and the handling of the subsequent investigation.
Other Troubles incidents continued to provide controversy. The collapse of a murder case concerning the 1989 shooting of lawyer Pat Finucane was followed shortly afterwards by the killing of the defendant, one-time informer William Stobie.
Meanwhile, the public inquiry into the Bloody Sunday deaths of 1972 moved slowly on, with Sinn Fein's Martin McGuinness admitting he had been a senior member of the IRA on the day of the shootings.Reuse content