Fabvier was born in 1783. He studied in Paris and served in the French Army during the Napoleonic Wars, rising to the rank of Colonel by the time he was 30 years old.
After the Bourbon restoration, he left the army and went to England. In 1823 he came to Greece to aid in the War of Independence against the Ottoman Empire. In 1825, he was made commander of the 4th Regular Greek Army at Nafplio. In August 1826, he took part in the Battle of Chaidari which ended in defeat but later in that year, on November 30, he managed to break through the siege of the Acropolis and supply the garrison defending it. On May 24, 1827 he finally surrendered the stronghold to the Turks.
Greece honoured Fabvier by making him an honourary Greek citizen in 1842 and awarding him the Great Cross of the Order of the Saviour (Μεγαλόσταυρος του Τάγματος του Σωτήρος).