In November 1934, 7,368 Protestants in east Donegal signed a Unionist petition to the British and Northern Irish governments requesting to transfer their region to Northern Ireland. This was a reaction to policies made in the Irish Free State by Fianna Fá il during the 1930s that resulted in the Economic War. News of this event spread to numerous newspapers across the British and Irish Isles, Australia, New Zealand, South Africa and Southern Rhodesia through Irish diasporas across the British empire. This was an exceptional event of southern Unionism in post-partition Ireland, displaying an element of defiance in their development of living in the Irish Free State. The work analyses the roots of the petition and those who organised the document. What were the terms of the petition? What did the petition manage to achieve and fail to resolve? How did it lead to a Derry– Donegal Milk War, which lasted three years?