The Holy Monastery of Pantocrator stands on the north-eastern side of the Athos peninsula, by the sea. Nearby is the site of the ancient city of Thyssus. Although age-long oral tradition maintains that it was founded by Alexius Comnenus, it is to be concluded from the surviving evidence that the founders of the Monastery were the brothers Alexius (who held the military rank of stratopedarches - camp commander) and Ioannes (a court official with the title of Great Primmicerius).
It is not known when building work was started, but by 1358 the Monastery was already in existence, and was restored probably in 1362 by the Patriarch Callistus I. Ancient monastic houses which were incorporated into the Pantocrator Monastery included those of St Auxentius, St Dorotheus, Kynopodos, Ravdouchou, Phakenou, and Phalakrou. Alexius died around 1368, and it appears that in 1384 Ioannes retired to the Monastery and was himself tonsured as a monk. The many donations made by the brothers paid for most of the metochia which the Monastery held until the middle of the present century. Also a gift of the brothers is the icon of Christ Pantocrator (Ruler of All), which is today in the Hermitage Museum in St Petersburg.
The Monastery was restored and extended in the 16th century with funds supplied by princes of the Danubian Provinces. In spite of owing huge debts during the Turkish occupation, the Pantocrator Monastery did not lose its vitality. Important and saintly figures chose it as their home, such as Patriarch Callistus II Xanthopoulos and Symeon, and Theonas, Archbishops of Thessaloniki. The Monastery was afflicted by fires in 1393, 1773, and 1948, fortunately without the destruction ever being total.
The katholikon, dedicated to the Transfiguration of the Saviour, was built together with the rest of the Monastery, but clearly followed its own independent course both in its architecture and in its wall-paintings, which date back to the third quarter of the 14th century, but were repainted in 1854. The bell-tower is a 19th-century building. The Monastery possesses a considerable collection of relics of saints, such as of Ioannicius of Olympus in Bithynia, Theodore the Commander, and Cosmas and Damian, a piece of the True Cross, and objects such as a part of the shield of St Mercurius, and icons of the 14th century onwards. The sanctuary screen may be the oldest in Mount Athos. The protecting icon of the Monastery is that of Our Lady Gerontissa, one of the Holy Mountain's miracle-working icons.
The Monastery's library contains some 350 manuscript codices and about 3,500 printed books. The Monasteries documents are in Greek and Turkish, and it also has one written in Vlach, dating from the 17th century. There are seven chapels in the Monastery and another seven outside its walls. Pantocrator has five kellia in the Karyes area. In modern times, the Monastery acquired many metochia in Greece, Asia Minor, and Wallachia, of which today it no longer possesses even one. Among the dependencies of the Monastery are the Skete of the Prophet Elijah, five kellia, and 38 kalyves in the region of Kapsala. The Monastery occupies seventh place among the monasteries of Athos. It returned to the coenobitic system in 1992. Today it has about 15 monks, who are making every effort to revive its life.