Breaking down the island's walls instead of building them

Why is there a United Ireland rugby team? 

Although soccer – in its national representative sides and its domestic leagues – could not resist the partition of Ireland, the reaction of the men who controlled rugby in Ireland to the partition of the island was to attempt to ignore it, at least insofar as they sought to place the playing of rugby outside politics.

The organisation of rugby since the 1880s facilitated this in that the provincial structure that had been operational by the end of that decade permitted an independence of action that suited those who controlled rugby in Ulster.