[GR3YFOXXX]

To be fair I was wrong about the Anglo-Irish treaty, I actually only studied the GoI 1920. To be honest though it is a fairly tangential issue. The GoI created an artificial Unionist majority in the north, so it is hardly surprising that they excercised their right to rejoin the UK.

[L i b]

(Original post by James82)
For 11 days Northern Ireland was part of the Irish Free State.

That's extremely controversial since for that period "the powers of the Parliament and the Government of the Irish Free State shall not be exercisable as respects Northern Ireland, and the provisions of the Government of Ireland Act, 1920, shall, so far as they relate to Northern Ireland, remain of full force and effect". The 1920 Act includes, for example, the statement that "the supreme authority of the Parliament of the United Kingdom shall remain unaffected and undiminished over all persons, matters, and things in Ireland and every part thereof".

It was a legally absurd situation, and it's not exactly illuminating to suggest that Northern Ireland changed country during that period.

[James82]

(Original post by L i b)
That's extremely controversial since for that period "the powers of the Parliament and the Government of the Irish Free State shall not be exercisable as respects Northern Ireland, and the provisions of the Government of Ireland Act, 1920, shall, so far as they relate to Northern Ireland, remain of full force and effect". The 1920 Act includes, for example, the statement that "the supreme authority of the Parliament of the United Kingdom shall remain unaffected and undiminished over all persons, matters, and things in Ireland and every part thereof".

It was a legally absurd situation, and it's not exactly illuminating to suggest that Northern Ireland changed country during that period.

It did change country de jure if not de facto, but the point is Northern Ireland had the choice to make it de facto and turned it down.

The United Kingdom never forced Northern Ireland to leave the Irish Free State, it was their own decision, just like it was the republic's decision to turn down Churchill's offer during WWII. So, both sides have refused a one state solution. It shouldn't be Westminster's decision to make, it should be up to Northern Ireland, which is how it has been for the last 90 years. If the people want to join the Irish Republic then that is up to them, but you only have to look at the opinion polls to see that the overwhelming majority of people in Northern Ireland don't want to.