However, it is the plantation of Ireland by Protestants from across the Irish Sea, dating from the reign of Queen Elizabeth I, to which the 20th-century troubles can be directly traced.
The suppression of Catholics by English and Scottish Protestant planters led to a series of revolts.
And the victory of the Protestant King William over the Catholic army of James VII and II at the Battle of the Boyne is celebrated by Orangemen to this day.
In 1916, Irish rebels took part in the Easter Rising, a rebellion against British rule that was crushed by the authorities. The execution of the ring-leaders inflamed Anglo-Irish tensions and Ireland was plunged into a bitter war of independence.
The war ultimately led to partition in 1921 and the creation of the Irish Free State and Northern Ireland.
The partition treaty proved hugely divisive and civil war followed before a period of relative peace.
Then, in the 1970s, violence erupted once more with the Northern Irish troubles, which was fuelled by a 35-year campaign of terrorism led by the Provisional IRA.