It lies on the west bank of the river Danube and nearly touches the eastern shore of Lake Balaton.

When this part of Hungary formed a Roman province called Pannonia, several settlements stood here: the capital was Gorsium, but there were other significant towns too, where present-day Baracs and Dunaújváros are (the towns were called Annamatia and Intercisa, respectively).

After 586 several nomadic people inhabited in the area, until Hungarians conquered it in the late 9th century.

The town of Fehérvár (modern-day Székesfehérvár) became significant as the seat of Prince Géza.

65,000 persons in Fejér County did not declare their ethnic group at the 2011 census.