The history of the city of Oradea is a long and interesting one. It was first settled by the Celts in the 4th century BC, and it was known as Arad. The Roman Empire conquered the city in the 1st century AD, and it was renamed Oradea. The city flourished under the Romans, and it became an important cultural and economic center. The city was captured by the Huns in the 5th century AD, and it was later conquered by the Magyars in the 9th century AD. The city passed into the hands of the Ottoman Empire in the 16th century AD, and it remained under Ottoman rule until the late 19th century. The city was liberated from Ottoman rule in 1867, and it became part of the Austro-Hungarian Empire. The city flourished under Austro-Hungarian rule, and it became an important industrial center. The city was partitioned between Hungary and Romania after World War I, and it became part of Romania. The city suffered heavy damage during World War II, but it was rebuilt after the war. The city became part of Romania again after the collapse of the Soviet Union in 1991.