Bellot was born in Paris, the son of a farrier, but moved to Rochefort with his family in 1831. With the aid of the authorities of Rochefort he was enabled at the age of 15 to enter the Ecole Navale at Brest, in which he studied two years and earned a high reputation. He then took part in the Anglo-French expedition of 1845 to Madagascar, and received the cross of the Legion of Honour for distinguished conduct. He afterwards took part in Anglo-French blockade of the Río de la Plata, that of Parana to South America, which opened the Río de la Plata to commerce.