After studying law and theology at Avignon, at that time belonging to the Papal States, he was made auditor of the Roman Rota by the favour of Pope Pius VI.
Meanwhile he had kept up a correspondence with the cardinal Secretary of State, informing him of all that passed in Paris and could be of interest to Pius VI.
When the nuncio, Antonio Dugnani, left Paris towards the end of 1790, the Pope appointed Salamon to be his internuncio at the Court of Louis XVI.
In 1801 Giovanni Battista Caprara arrived in France as papal legate and appointed him administrator general of the dioceses of Normandy.
The new pontiff, Pope Pius VII, did not select him for one of the sees under the Concordat, but made him titular bishop of Orthosia of Caria.