In 1919, Doroshenko went into exile and eventually settled in Prague where the Czechoslovak government gave refuge to Ukrainian and Russian emigres, especially scholars.

In 1937 and 1938, he made two highly successful lecture tours of Canada which at that time possessed a large Ukrainian immigrant population.

In 1947, he moved to Canada where he taught history and literature at Saint Andrew's College in Winnipeg and together with the literary historian, Leonid Biletsky, and the philologist, Jaroslav Rudnyckyj, established a branch of the Ukrainian Free Academy of Sciences.

On the one hand, he accepted the historical scheme of the famous Ukrainian historian, Mykhailo Hrushevsky, which saw continuity in the history of his country from Kyivan Rus' to modern times and claimed the heritage of Kyivan Rus' primarily for modern Ukraine, but on the other hand, he rejected Hrushevsky's stress upon the role of the common people, instead stressing the role of the educated political elite.

Doroshenko was especially fond of the old Cossack officer class which evolved into the later Ukrainian gentry and he gave much space in his histories to the strivings of this elite for political autonomy and independence.