3rd century BC Illyrians and Celts establish settlements on the banks of the Drava, near present-day Osijek
133 Roman Emperor Hadrian establishes Colonia Aelia Mursa, a mixed military-civilian settlement on the site of present-day Osijek’s Donji Grad.
380 Mursa is sacked by the Goths
7th century Migrating Slav tribes settle throughout southeastern Europe. Among them are the Croats, who occupy Slavonia, the Adriatic coast, and much of Bosnia.
8th century Eastern Slavonia becomes part of the Bulgarian Empire
9th century Eastern Slavonia falls under the rule of Croatian kings
1102 Croatia forms a dynastic union with Hungary
1196 Osijek is mentioned for the first time in historical sources as “Essek”, a port and trade centre under the rule of Hungarian King Emerik.
1241-2 Slavonia is ravaged by the Mongols
13th-14th centuries Osijek emerges as an important fortress town under powerful local magnates the Korogyi family.
1526 The Ottoman Turks capture Osijek from the Hungarians.
1566 In order to cross the marshlands northeast of town, the Turks construct a 8km-long wooden bridge from Osijek to Darda. Featuring watch-towers and rest-stations, the bridge become one of the wonders of European engineering.
1600s Osijek becomes famous for its 8-day-long spring fair, which attracts thousands of merchants from all over the Ottoman Empire.
1664 In fighting between the Habsburg and Ottoman Empires, Croatian noble Nikola Šubić Zrinski leads a unit into eastern Slavonia and burns down the wooden bridge.
1687 Habsburg armies under Count Nicholas Lodron drive the Ottoman Turks out of Slavonia, liberating Osijek on 26 September.Austrian and German settlers arrive in the army’s wake, re-populating the town. The Habsburgs incorporate Osijek into the so-called Military Frontier, a belt of territory bordering on the Ottoman Empire which is placed under the direct rule of Habsburg generals. Osijek becomes the headquarters of the Military Frontier’s eastern sector.
1712-22 Construction of the Tvrđa, the fortified complex that serves as the Military Frontier’s eastern HQ.
1738-39 Bubonić plague kills an estimated 50% of Osijek’s population.
mid-1700s Eastern Slavonia is re-populated with Croats, Czechs, Slovaks and Germans, summoned here by Habsburg Empress Maria Theresa to boost agriculture and trade.
1783 Habsburg Emperor Josef II moves the Military Frontier’s eastern HQ from Osijek to Petrovaradin (near Novi Sad in Serbia).
1779 A new road from Osijek to Budapest boosts the local economy.
1800s. Osijek becomes a thriving multi-cultural metropolis. Croatian, German and Hungarian words are mangled together to form a uniquely polyglot local slang known as Essekerski.
1900 The consecration of the Church of SS Peter and Paul, the tallest structure so fasr built in Osijek.
1907 A branch of the Croatian National Theatre opens in Osijek
1918 The Habsburg empire collapses, and Osijek becomes part of the new Kingdom of Serbs, Croats and Slovenes – subsequently re-named Yugoslavia.
1923 Osijek city authorities begin demolishing the 18th-century fortifications, establishing riverside parks in their place.
April 1941 Yugoslavia falls to Nazi Germany and her allies.
April 1945 Communist partisans liberate Osijek from the Nazis.Croatia once more becomes part of Yugoslavia, this time as a federal republic of a one-party socialist state.
1950s Osijek emerges as a major industrial centre producing, among other things, most of Yugoslavia’s soap and matches
May 1980 Yugoslavia’s authoritarian ruler Josip Broz Tito dies, ushering in a decade of stagnation and uncertainty
April 1990 With faith in communist Yugoslavia ebbing away, multi-party elections in Croatia are won by the pro-independence HDZ.
19 May 1991 A nationwide referendum produces an overwhelming majority in favour of Croatian independence from Yugoslavia
26 June 1991 Croatia declares independence
August 1991 The Yugoslav Army, supported by Serbian paramilitaries, begins an invasion of eastern Slavonia.
November 1991 The east-Slavonian town of Vukovar falls to Yugoslav-Serb forces, who then advance on Osijek, subjecting the city to a 9-month siege. Osijek remains a front-line city, exposed to periodic shelling, throughout the war.
August 1995 Croatian victories on the battlefield bring the Croat-Serb conflict to an end.
1995-2006 Osijek slowly resumes its position as the economic and cultural capital of Croatia’s southeast.