Altbayern mainly consists of the following Bavarian Regierungsbezirke (administrative regions): Since the term Altbayern is based on the cultural difference compared to Franconia (i.e. Upper, Middle and Lower Franconia) as well as with Swabia (i.e. Bavarian Swabia), some areas surrounding the Upper Franconian town of Wunsiedel as well as the Swabian Aichach-Friedberg district are counted as part of Altbayern, because they share the same history, dialect and culture as the three previously mentioned districts.

Strictly speaking, the Upper Austrian Innviertel also belongs to Altbayern, since it was part of the Bavarian electorate until it was attached to the Archduchy of Austria according to the 1779 Treaty of Teschen.

The spelling "Baiern" was changed to "Bayern" at the start of the reign of King Ludwig I, firstly due to his love for Ancient Greek culture, [clarification needed] and secondly to reflect the recent annexation of large, previously non-Bavarian areas like Swabia and Franconia.

The Franconian and Swabian territories were not merged into the Kingdom of Bavaria until the German mediatisation, and the 1815 Congress of Vienna, hence they still have strong cultural as well as linguistic differences from Altbayern.

[1] On Bayerischer Rundfunk television a regular program called "Schwaben & Altbayern" that discusses current political and cultural topics of Bavaria's southern regions.