During his teenage years Spiro attended the Bulgarian Men's High School of Thessaloniki, then part of the Ottoman Empire. In 1912 Skopje was ceded to Serbia where the Macedonian Slavs were faced with the policy of forced serbianisation. When during World War I Bulgaria occupied Macedonia (1915 - 1918) his father, Georgi Kitinchev became a mayor of Skopje. At the same time he studied in Lausanne, Switzerland. Spiro was involved there in the organization of Macedonian students called MYSRO. In 1919, during the meetings of the Paris Peace Conference, the MYSRO issued appeale in favor of an independent multiethnic Macedonian state, based on the principle of the Swiss Confederation.