At that time Kazan had 146.000 inhabitants. For the defence of Kazan Reds concentrated about 10 thousand men from all the region. The most effective of the defending troops were "international" detachments: Latvian Riflemen (two regiments), Karl Marx's International Battalion (made from Austrians and Hungarians prisoners, captured by Russians during First World War), the First Moslem Communist Battalion, First Tatar-Bashkir Battalion etc.
