Osijek is a city in eastern Croatia and the administrative center of the Osijek-Baranja County. It is located near the confluence of the Drava and the Danube rivers, and is the fourth largest city in Croatia. Osijek has a rich history, having been inhabited since the Neolithic period, and it has played an important role in the region's development throughout the centuries.
The earliest known settlement in the area of Osijek dates back to the Neolithic period. The settlement was located on the banks of the Drava River, and it was inhabited by the Illyrian tribe of the Andizetes. From the 5th century BC, Osijek was part of the Roman province of Pannonia, and it was later occupied by the Huns, the Ostrogoths, and the Avars. In the 9th century, the area was part of the Slavic state of Lower Pannonia, and in the 10th century it was part of the Kingdom of Croatia.
In the 12th century, Osijek was part of the Kingdom of Hungary, and it was granted the status of a free royal city in 1254. In the 15th century, it became a major center of trade and commerce, and it was also an important military fortress. In the 16th century, Osijek was occupied by the Ottoman Empire, and it remained under Ottoman rule until 1687, when it was liberated by the Habsburgs.
In the 18th century, Osijek became part of the Habsburg Empire, and it was one of the most important cities in the region. During this period, the city's economy flourished, and it became an important center of trade and manufacturing. In the 19th century, Osijek was the largest city in Croatia, and it was also the center of the Croatian National Revival movement.
In the 20th century, Osijek was occupied by the Axis powers during World War II, and it was then annexed to Yugoslavia in 1945. After the breakup of Yugoslavia in the 1990s, Osijek became part of the newly independent nation of Croatia. Today, Osijek is a vibrant city, and it is an important cultural, economic, and educational center in the region.