Theodo I of Bavaria

Theodo (about 625 – 11 December c. 716) also known as Theodo V and Theodo II, was the Duke of Bavaria from 670 or, more probably, 680 to his death. It is with Theodo that the well-sourced history of Bavaria begins. He strengthened his duchy internally and externally and, according to the medieval chronicler Arbeo of Freising, he was a prince of great power whose fame extended beyond his borders.

Theodo's descendance has not been conclusively established. A member of the Agilolfing dynasty, his father possibly was Duke Theodo IV of Bavaria (d. 680) and his mother was probably Fara of Bavaria (b: 600), daughter of one of the Kings of the Lombards and by her mother a grandaughter of Gisulf I of Friuli (b: 577).

Theodo established his capital at Ratisbona (modern Regensburg). He married Folchaid, of the Frankish (possibly Robertian as the daughter of Robert II) aristocracy in Austrasia, to build diplomatic ties there. He intervened in Lombard affairs by harbouring the refugees Ansprand and Liutprand, whom he assisted militarily on his return to claim the Iron Crown. Liutprand later married his daughter Guntrude. Theodo also defended his duchy ably from the Avars (with some failure in the east).

Theodo is the patron to the four great missionaries of Bavaria: Saint Rupert, Saint Erhard, Saint Emmeram, and probably Saint Corbinian. He was the first to draw up plans for the Bavarian church, aiming both at a deeper cultivation of the countryside as well as greater independence from the Frankish Kingdom by a closer association with the Pope. He was the first Bavarian duke to travel to Rome, where he conferred with Pope Gregory II. The diocesan seats were placed in the few urban centres, which served as the Duke's seats: Regensburg, Salzburg, Freising and Passau.

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