Olsztynek [ɔlʂˈtɨnɛk] (Masurian: Ôlstÿnek; German: Hohenstein in Ostpreußen)[citation needed] is a town in northern Poland, in Olsztyn County, in the Warmian-Masurian Voivodeship.

Grand Master Winrich von Kniprode granted the surrounding settlement town privileges according to Kulm law in 1359.

During the Polish–Lithuanian–Teutonic War, the 1410 Battle of Grunwald took place in the vicinity of the town, whereby the Poles and Lithuanians defeated the Teutonic Knights.

Quickly rebuilt afterwards, the citizens however had to face high taxes imposed by the Knights who had to refinance their contributions paid according to the 1411 Peace of Thorn.

Since 1618 ruled in personal union with the Imperial Margraviate of Brandenburg as Brandenburg-Prussia, although the Prussian part remained under Polish suzerainty until 1657.

[5] During the Napoleonic Wars in 1807 the French stayed in Olsztynek, including Marshals of France Michel Ney and Pierre Augereau.

[6] From 1903 to 1933 the Tuberculosis sanatorium Hohenstein for male patients operated in the municipal forest about 4 km north of the town center.

[5] As a condition of the Treaty of Versailles, the League of Nations held the East Prussian plebiscite on 11 July 1920 to determine if the people in the southern districts of the East Prussian province wanted to remain within the Free State of Prussia and Germany or to join the Second Polish Republic, which just regained independence after World War I.

[8] In remembrance of the 1914 battle a large Tannenberg Memorial was inaugurated here on 18 September 1927, and made the place of the burial of Reich President Paul von Hindenburg on 7 August 1934.