 After he had moved back to Pavia, he became the leader of the left-wing split of the Socialist Party and then the secretary of the newborn Communist Party of Italy (later to be known as the Italian Communist Party) and founder and director of the Pavesan Federation of that party in 1921.Ghinaglia was a person who asserted the necessity of resistance to the Fascist violence.On the 21 April 1921, Ghinaglia fell victim to a Fascist vendetta and was found dead by a gunshot wound to the head on the bridge overlooking the Ticino River.