Short answers, pulled from the story.
Antoine Christophe Saliceti was a French politician and diplomat born on the 26th of August 1757 in Saliceto, Haute-Corse, who served during the Revolution and the First Empire. He began his career as a lawyer at the upper council of Bastia and rose to become a deputy to the Estates-General of 1789, a Montagnard in the National Convention, and eventually minister of police and war in the Kingdom of Naples.
Yes. On the 15th of January 1793, Saliceti voted for the death of King Louis XVI as a deputy to the National Convention.
Saliceti met Napoleon Bonaparte while both were in Provence and actively promoted his compatriot's career. Despite opposing Napoleon's 18 Brumaire coup in 1799, Saliceti was retained by Napoleon as a representative to Lucca and Liguria, where he helped engineer territorial annexations to the Empire.
Saliceti had been a close associate of Maximilien Robespierre, and when the Thermidorian Reaction toppled the Robespierre faction he was denounced. He was saved only by the amnesty issued by the French Directory.
Saliceti followed Joseph Bonaparte to the Kingdom of Naples in 1806, after Joseph had been imposed as king. He served there as minister of police and minister of war until his death on the 23rd of December 1809.
Saliceti died in Naples on the 23rd of December 1809 in mysterious circumstances. The cause has never been definitively established, and he may have been poisoned.