Ireland gained its independence and was partitioned, with Northern Ireland remaining within the United Kingdom, at about the same time as the Kurds were incorporated into modern Iraq nearly a century ago.
For several decades, the UK pretty much ignored Northern Ireland and Ireland went its own way. What is euphemistically called "The Troubles" erupted in the late 1960s in Northern Ireland and a nasty little war claimed nearly 4,000 lives in a small place over three decades.
Relations between Ireland and the UK were at a low ebb for many decades but the destabilising conflict in the north of the island of Ireland, plus bombs and assassinations on the British mainland as well as attacks in the Irish Republic forced the two countries into an ever deepening political relationship.
The long process of peace making begun in earnest in the early 1970s but it took much longer to end terrorism by Irish republican and pro-British loyalist organisations - some small groups continue to maim, bomb and kill but not on the same scale as before.
The crucial period of change came in the early 1990s with the arrival on the scene of American diplomats, who stayed clear while the Cold War was in full swing because they didn't wish to offend their British partners.
Peace in Northern Ireland and ever closer Anglo-Irish relations owe much to two overlooked heroes of the 1990s - the Conservative Prime Minister John Major and his Northern Ireland Secretary Peter Brooke.
Among others who can claim credit is the British-Irish Parliamentary Assembly, founded in 1990. It encompasses about 70 parliamentarians from 8 assemblies across the British archipelago but chiefly Ireland and Great Britain. It's a fairly unique body.
Its initial meetings reflected the often poisonous state of Anglo-Irish relations but these are now extraordinarily close. Political co-operation has been tested in decades of work on Northern Ireland. This experience has modified attitudes to the north which is going its own devolved way but with the two countries as guarantors.
Irish revanchism gave way to practical efforts to build north-south relations and to reconciliation. The British stressed that they had "no selfish strategic or economic interest" in Northern Ireland but could facilitate unification if it is ever desired.
The Assembly's twice-yearly plenaries help deepen official Anglo-Irish relations. Former Northern Ireland Secretary Paul Murphy says: "the lives of people in Northern Ireland were improved by the Assembly which can spread best practice, for instance, on health or education from each jurisdiction."
Sinn Fein TD Aengus O Snodaigh argues: "We are two islands on the edge of Europe. The more we co-operate the better for all of us. Decisions in one place have a major impact on others." The Assembly Co-Chair and Irish Deputy Joe McHugh says: "the importance of the Assembly is using the wisdom of senior politicians to cultivate and energise a new generation of parliamentarians."
They were certainly energised by Judith Gillespie, the Deputy Chief Constable of the new police service, the PSNI. She said this is the most accountable police service in the world, nearly 30% of its officers are female, ordinary crime is low and "the combined total for deaths, bombings, shootings and paramilitary style assaults in 2012 could be fitted into one day in 1972 - the peak year of the Troubles when almost 500 people were killed."
Most of Northern Ireland is peaceful with what Labour's Baroness Blood calls an "extraordinary" rise in the number of mixed marriages between Catholics and Protestants. But she recognises that sectarianism, sometimes in children of two, is stubborn in some areas, alongside more peace walls that separate Catholics and Protestants than before the 1998 Good Friday Agreement.
This was a necessary but insufficient step in that it insisted on mandatory coalitions without the politically refreshing role of an Opposition. I asked May if she thought that there should be an opposition. She retorted that "a government that works would be better."
The old zero-sum mentality, where Catholics and Protestants resent successes for each other, obstructs progress. Critics charge that the government is more about the sharing out of power and fiefdoms between two suspicious blocs than collective responsibility.
Northern Ireland has come far but deep-set problems persist and will for some time to come, given the enormity of the pain felt by so many. Such problems are best overcome within the province but the experience and expertise amassed by the Assembly should help.
I'm not sure if there are specific lessons for the Kurdistan Region in its relations with Baghdad or any of its neighbours apart from noting that once intractable conflicts can be solved through diligent statesmanship. And that the Assembly, along with many other organisations, has challenged the ancestral voices of hatred and grievance and is making a positive case for cross-border co-operation.