In the postwar period, Shaw despaired of the British government's coercive policies towards Ireland, and joined his fellow-writers Hilaire Belloc and G. K. Chesterton in publicly condemning these actions. The Anglo-Irish Treaty of December 1921 led to the partition of Ireland between north and south, a provision that dismayed Shaw. In 1922 civil war broke out in the south between its pro-treaty and anti-treaty factions, the former of whom had established the Irish Free State. Shaw visited Dublin in August, and met Michael Collins, then head of the Free State's Provisional Government. Shaw was much impressed by Collins, and was saddened when, three days later, the Irish leader was ambushed and killed by anti-treaty forces. In a letter to Collins's sister, Shaw wrote: "I met Michael for the first and last time on Saturday last, and am very glad I did. I rejoice in his memory, and will not be so disloyal to it as to snivel over his valiant death". Shaw remained a British subject all his life, but took dual British-Irish nationality in 1934.