Transiurania), southeast of (Latin: trans in the sense of 'beyond') the Jura Mountains, together with the adjacent County of Burgundy (modern region of Franche-Comté) to the northwest.

[1][2][3][4] Transjurania originally was a duchy of the Carolingian Empire, covering the Central Plateau from the Jura Mountains up to the Great St Bernard Pass in the Western Alps.

Together with the Burgundian comital estates around Besançon and Dole on the Doubs river northwest of the Jura range, the Transjurane territories became part of the short-lived Middle Frankish realm of Emperor Lothair I upon the 843 partition by the Treaty of Verdun.

The Transjurane duchy was then ruled by Hucbert, a scion of the Bosonid dynasty, the younger son of Count Boso the Elder of Arles, and through his sister Teutberga brother-in-law to King Lothair II.

When Lothair II died without heirs in 869, his Lotharingian realm was divided into a West and East Frankish part between his uncles Charles the Bald and Louis the German by the 870 Treaty of Meerssen.

[5] Emperor Charles the Fat, son of Louis the German, by 884 had once again reunited all Carolingian territories, except for the Lower Burgundian Kingdom of Provence established by Boso of Vienne in 879.

From this point, Rudolph II began to campaign in the Kingdom of Italy, allied with the rebellious margrave Adalbert I of Ivrea and defeated Emperor Berengar I at Fiorenzuola in 923.

In the tense situation, Rudolph's father-in-law Duke Burchard II of Swabia hurried to help, but was killed at Novara by the henchmen of Archbishop Lambert of Milan.