The Mosul Vilayet was part of the Ottoman Empire until the end of the First World War. Following the war it was occupied by Britain and the Vilayet became the bone of contention between the Ottoman Empire and Britain. After the War of Independence, the new Turkish Republic considered Mosul one of the crucial issues determined in the National Pact. Despite constant resistance, Britain managed to bring the issue into the international arena, scaling it down to a frontier problem between Turkey and Iraq. In the Turkish historical literature, the Mosul Question has been studied until the Frontier Treaty (1926). According to these studies, the Turkish government, in accordance with the exchange of letters annexed to the Frontier Treaty (1926), agreed to receive a fixed cash settlement of 500,000 pounds, rather than calculating the amount on a ten percent basis. That is to say, the Turkish government received the 500 000 pounds and the folio of the Mosul Question was closed. But some findings proved that this was not the case. Some figures in the Turkish state budgets indicate that Turkey received payments on a ten percent basis instead of the fixed cash settlement. From 1931 to 1952 Turkey received royalty payments regularly. After 1952, two issues caused serious problems between Turkey and Iraq; namely, the unpaid years and insufficient payments. In latter period, Turkey chose to pursue a conciliatory policy and the issue was put aside for the purpose öf establishing friendly relations with Iraq.