After studying at the archdiocesan seminary of Perugia, Rossi took part in the First Italian War of Independence as a military chaplain for the Perugia volunteers. Back in Perugia, he maintained a long correspondence with the government of the Roman Republic, which at the time seized power in the city of Rome and expelled the Pope. This caused Rossi to be suspended from his clerical position by Pope Pius IX and removed from his teaching job.