Was Leon Trotsky ever a member of the proletariat?
Not really. He was the fifth child of a fairly well off farmer in a small village in what is now Ukraine. His father sent him off to Odessa to school aged 9, and he left fluent in Russian, Ukrainian and able to speak German and French. So it is arguable that he was from the “toiling classes” or from petty bourgeois origins, but it would be stretching it to say he was a member of the proletariat. After school he became a professional revolutionary, and he carried on with this “career” until the October Revolution when he became Commissar for Foreign Affairs. So he never had a conventional job, let alone a working class one.