Soviet motives for entering Spanish Civil War

analyze the motives which prompted the USSR to intervene in the Spanish Civil War on the side of the Republican Government, in 1936 (a topic my professor has approved).

take the view that Soviet foreign policy was not guided by a well planned ‘meta-strategy’ of Collective Security, but was shaped incrementally based on such factors as ideological commitment, financial interests, geostrategic interests, Stalin’s personal motives etc.

Our course syllabus states the essay is to be "10 pages, double-spaced with an introduction, main part, conclusion, and bibliography", but does not go into any detail regarding the essay topic. Hence, the essay is relatively open-ended.

The focus of the paper must be on Soviet involvement, motives, actions etc. (not on those of other countries involved in the conflict).