Eger has been inhabited since the Stone Age. Today's Eger was formed in the 10th century by St. Stephen (997–1038), the first Christian king of Hungary, who founded an episcopal see in Eger. The first cathedral of Eger was built on Castle Hill, within the present site of Eger Castle. Eger grew up around its former cathedral and has remained an important religious centre in Hungary since its foundation. The 14th-16th centuries were an age of prosperity for Eger. Winegrowing, which the town is still famous for, began to be important around that time. The bishops of Eger built beautiful buildings in the city during 18th and 19th centuries.
During the Turkish advance into Central Hungary, Eger became an important border fortress, successfully defended by Hungarian forces in the 1552 Siege of Eger. The first writer of note to draw on the story was the Hungarian renaissance poet and musician Sebestyén Tinódi Lantos (c. 1510–1556), whose account may have come partly from eye witnesses. Most Hungarians know best the version of this story found in the 1899 novel "Eclipse of the Crescent Moon" (Hungarian "Egri csillagok", lit. "Stars of Eger") by the 19th century Hungarian author Gárdonyi Géza, which is set reading under the Hungarian national curriculum.
However, Eger was attacked in 1596 by a bigger army of Turks, who took over the castle after a short siege. Then followed 91 years of Ottoman rule in which Eger was the seat of the Turkish Eger Eyalet (administrative division). Churches were converted into mosques, the castle rebuilt, and other structures erected, including public baths and minarets.
The rule of the Turks in Central Hungary began to collapse after a failed Ottoman attempt to capture Vienna. The Vienna-based Habsburgs, who controlled the rest of Hungary, apart from Transylvania, steadily expelled the Turks from the country. The castle of Eger was starved into surrender by the Christian army led by Charles of Lorraine in 1687,
