The article presents attempted comparative analysis of different types of federalism against the background of long historical trends. Viewing federalism in the broad context of history of the Western political form, the author finds out substantial deviations of the federative model from the ideal type of sovereign state and, in the meantime, its close affinity with the imperial type of political organization. On qualifying the early European (the Swiss and the Dutch) federalism as atavistic, “descendant from empire”, the author pays most attention to American federalism, the one which emerges not at the time when empire is already undesired, but when it is not yet possible. According to the author’s conclusion, this unique federalism, “ascendant towards empire”, proved one of the sources of the American might.