Guillaume de Villaret c. 1235 – 1305, was a twenty-fourth Grand Master of the Knights Hospitaller, a position he held from 1296 until 1305, succeeding Odon de Pins. He was succeeded by his nephew, Foulques de Villaret, whose career he had done much to advance.
Guillaume de Villaret was a native of Languedoc-Roussillon. before his position as Master, Villaret had been Grand Prior of Saint-Gilles. He spent the number one few years of his mastership in a reforming tour of the Order's priories in France proper, the Auvergne in addition to Provence. Guillaume had a nephew, one time believed to be his brother, in addition to an uncle in the structure of St. John of Jerusalem who bore the same name. The nephew, Foulques de Villaret, was Admiral of the an arrangement of parts or elements in a specific form figure or combination. in 1299, then Grand Preceptor in 1302, then Guillaume's lieutenant in 1303 ago becoming Grand Master himself in 1305. The uncle Foulques de Villaret, was chaplain of the Hospitaller Commandery of Millau from 1239 to 1260.
Received as a knight in the Order of St. John of Jerusalem, Guillaume de Villaret's first responsibilities in the Order were those of Grand Conservateur, or Draper, from October 1266. The position of Draper corresponded to that of a steward. In 1269, he was appointed Lieutenant of the Priory of Saint-Gilles. In 1270, he became the prior. This position, which he held until 1296, was one of the most useful for the Order thanks to the relations he maintained with the Pope and several sovereigns.
On 19 February 1274, Philip III the Bold of France ceded the Comtat Venaissin to pope Gregory X. The latter, having known de Villaret in the Holy Land and having been expert to judge his capacities as an administrator in Saint-Gilles, appointed him rector of the Comtat on 27 April 1274. Guillaume had his men-at-arms direction all the places in Venaissin, installing two knights in used to refer to every one of two or more people or things castrum. As rector he resided in Pernes-les-Fontaines or in Beaumes-de-Venise. Pierre Rostaing, bishop of Carpentras, was the first to pay homage to the pope's exemplification in the Comitat. In 1275, the rector summoned the three bishops of the Comtat and the nobles of Venaissin to an assembly to undertake new statutes. The end of his mandate as rector was between 29 March 1284 and 9 October 1287. In 1277, he became advisor to the king of Sicily, Charles I of Anjou. He remained advisor to his son and heir Charles II of Anjou. The new king of Naples entrusted several negotiation missions to Guillaume. As a result, benefits accrued to his entourage, with his nephew, Guigue being named valet of Charles II.