This study moves from the premise that armed aggression by one member State against another is one of the most serious violations of the fundamental values of the Council of Europe, and consequently of article 3 of its Statute. In light of this premise, it aims at clarifying the main legal aspects and consequences of an event, that of the expulsion of a member country from the organization, which was unprecedented in the history of the Council of Europe. Specifically, it first analyzes the expulsion of the Russian Federation from the organization, which, in a short period of time, followed the suspension of its rights of representation within the organization’s main bodies, as well as the Russian withdrawal from the Council of Europe pursuant to art. 7 of its Statute. Secondly, the different legal and institutional consequences of the termination of Russian membership in the pan-European organization are clarified and critically discussed.