Buda. Their courts, which were similar to the royal courts of Buda and Visegrád, were visited by such kings, scientists, and artists as Louis the Great, Sigismund of Luxembourg, King Matthias Corvinus, Galeotto Marzio, Regiomontanus, the famous astronomer Marcin Bylica and Georg von Peuerbach, Pier Paolo Vergerio and Antonio Bonfini, King Matthias's historian, who, in his work praises the constructive work of János Vitéz, King Matthias's educator. He had a library and an observatory built next to the cathedral. As Bonfini wrote about his masterpiece, his palace and terraced gardens: "he had a spacious room for knights built in the castle. In front of that, he built a wonderful loggia of red marble. In front of the room, he built the Chapel of Sibyls, whose walls were decorated with paintings of the sybils. On the walls of the knights' room, not only the likeness of all the kings could be found, but also the Scythian ancestors. He also had a double garden constructed, which was decorated with columns and a corridor above them. Between the two gardens, he built a round tower of red marble with several rooms and balconies. He had Saint Adalbert's Basilica covered with glass tiles". King Matthias's widow, Beatrix of Aragon, lived in the castle of Esztergom for ten years (1490–1500). The time of the next resident, Archbishop Tamás Bakócz (d. 1521) gave the town significant monuments. In 1507 he had Italian architects build the Bakócz chapel, which is the earliest and most significant Renaissance building which has survived in Hungary. The altarpiece of the chapel was carved from white marble by Andrea Ferrucci, a sculptor from Fiesole in 1519. The Ottoman conquest of Mohács in 1526 brought a decline to the previously flourishing Esztergom as well. In the Battle of Mohács, the archbishop of Esztergom died. In the period between 1526 and 1543, when two rival kings reigned in Hungary, Esztergom was besieged six times. At times it was the forces of Ferdinand I or John Zápolya, at other times the Ottomans attacked. Finally, in 1530, Ferdinand I occupied the castle. He put foreign mercenaries in the castle, and sent the chapter and the bishopric to Nagyszombat and Pozsony (that is why some of the treasury, the archives and the library survived). In 1543 Sultan Suleiman the Magnificent attacked the castle and captured it. The castle then remained under the Ottoman Empire. Esztergom (as Estergon)