Berthold II of Zahringen

Berthold II (c. 1050 – 12 April 1111), also known as Berchtold II, was the Duke of Swabia from 1092 to 1098, then the Duke of Zähringen from around 1100 until his death in 1111.

Berthold was a younger son of Berthold I of Zähringen and initially supported Rudolf of Rheinfelden against King Henry IV. In 1077, both the Zähringer and Rheinfeldener were relieved of their titles and possessions by the king. Berthold I of Zähringen died in 1078 and his son Berthold inherited his claims, including a claim to the Duchy of Swabia. In 1079, Berthold married Agnes, Rudolf's daughter.

In the following years, he became a strong supporter of Rudolf's eldest son, Berthold of Rheinfelden, against the king. He was also at odds with Frederick of Büren and the Bishops of Basel and Strasbourg. However, when the region quieted down in the late 1080s, Berthold is found as a witness to an exchange of land involving the Bishop of Basel (1087).

Tensions rose again in 1090, when Berthold of Rheinfelden died. At that point, Berthold of Zähringen asserted his claims to the Rheinfeldener inheritance in Burgundy, but not their titles, which went to Berthold of Rheinfelden's younger brother, Otto von Wetter(au)-Rheinfelden. He also placed a claim on the Duchy of Swabia. Supported by the Welfs and the Papacy, he was elected duke in opposition to Frederick in 1092. In that same year, he was chosen as Duke of Carinthia and Margrave of Verona (like his father) by those who opposed Duke Henry V. Berthold, also like his father, never held any real power in Carinthia.

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