This study discussed the issue of Turkey’s border relations with Syria, Iraq and Iran from 1923 until 1940. Several parameters were effective on shaping these relations or changing their course. The first of these parameters, the de facto Iraq’s border with Syria and Turkey was not drawn legally by the Lausanne Treaty. The French and English mandate governments established over Syria and Iraq respectively were far from displaying a friendly attitude in the process of drawing the borders. Their weapon against Turkey in that period was to encourage and provoke the Kurdish separatism. Another matter affecting Turkey’s border relations with neighboring countries was the responsibility of a new state established by a nation that had just come out of long battles, to fulfil a very difficult mission like providing safety and order throughout a border line of thousands of kilometers in the steepest geography within a short time. In other words the conditions of the era and the region were not appropriate for idealizing border relations with neighboring countries at all. 

Good or bad relations on the Turkey-Syria border depended on good or bad relations of Turkey with France which established a mandate government in Syria. France supported activities of the gangs established on the Syrian border with the purpose of pillaging and the ideal of Kurdish separatism against Turkey. Indeed this was experienced despite the treaty of amity that France concluded with Turkey several times on various dates. A treaty was concluded between France and Syria on 9 September 1936 for the sake of Syria’s independence. The treaty brought up the issue concerning the status of the Sancak region, which would continue between Turkey and France until 1939. France displayed an anti-Turkish attitude in the beginning; however, they began to give positive responses to the demands of Turkey when the World War 2 broke out, because they did not intend to lose the Turkish Government in this geography. As a matter of fact, with the relations ameliorating, the Hatay state which was established in the Sancak region, decided to join Turkey in 1939. Amelioration of the Turkey-France relations before the World War 2, not only enabled Turkey to get what they needed concerning the issue of Hatay. It also reduced the anti-Turkish activities of the gangs and organizations supported by France since the proclamation of the Republic throughout the border line, significantly. The Hoybun Association, which was one of these organizations, considerably lost their areas of activity and influence with the outbreak of the World War 2 and finally dispersed in 1946. This shows that as long as diplomatic relations between two neighboring countries are good, many of the possible safety issues along the border line can be solved. 

The Iraq border of Turkey has always been active since 1923. During the times when Iraq was under the rule of Britain, the British conducted activities offending the Turks first with Mosul issue and then supporting the spread of Kurdish separatism. For that purpose they continuously supported the anti-Turkish Nasturi and Kurdish elements in the region. The relations between Iraq and Turkey ameliorated after the British rule. In this context a consensus was made to act in unison against the tribes damaging both countries. This consensus was occasionally put into practice and very important goals were achieved regarding border safety. 

The relations of Turkey with Iran in the 1920s were not good due to the border safety. Together with the change of administration in Iran and amelioration of the relations between the two countries, many incidents violating order and safety on the border in the 1930s were prevented. However, this did not last long. Many incidents aimed at pillaging occurred on the Turkish-Iranian border at the beginning of the 1940s. However, it should be noted that while some of the order-related incidents observed on the Iranian border during the first years of the Republic were led by famous Kurdish tribal leaders, the incidents in the 1940s were completely aimed at pillaging. In addition we can say that these incidents were influenced by the world conditions. It is because Iran was occupied by Western states during that war in 1941. Thus it was not possible to expect Iran which experienced such problems, to provide border security as in the 1930s. 

It is possible to state that as well as military and administrative measures were taken throughout the border lines, successful foreign policies were also effective on the amelioration of the relations of Turkey with its neighbors during that period.