His mother was the first cousin of Jacob Frank, who claimed to be the Jewish messiah and founded the Frankist sect.
[citation needed] In 1792, in the wake of the French Revolution, he traveled via Strasbourg to Paris and became a Jacobin, changing his name, once again, to Junius Frey.
The new name derived from Junius from the Roman Junii family that fostered the famous tyrant slayer Brutus, and Frey being a transliteration of the German word for "liberty".
In June 1793 he published his book Philosophie sociale, dédiée au peuple françois.
[citation needed] He was arrested for treason and espionage and executed by guillotine on 5 April 1794 in connection with the case against his brother-in-law François Chabot.