In the fifteenth century, Guillaume d'Estouteville, a cardinal and Apostolic legate, reformed the university, correcting its perceived abuses and introducing various modifications. This reform was less an innovation than a recall to observance of the old rules, as was the reform of 1600, undertaken by the royal government with regard to the three higher faculties. Nonetheless, and as to the faculty of arts, the reform of 1600 introduced the study of Greek, of French poets and orators, and of additional classical figures like Hesiod, Plato, Demosthenes, Cicero, Virgil, and Sallust. The prohibition from teaching civil law was never well observed at Paris, but in 1679 Louis XIV officially authorized the teaching of civil law in the faculty of decretals. The "faculty of law" hence replaced the "faculty of decretals". The colleges meantime had multiplied; those of Cardinal Le-Moine and Navarre were founded in the fourteenth century. The Hundred Years' War was fatal to these establishments, but the university set about remedying the injury.