Otto I, a member of the House of Andechs, was Duke of Merania from 1204 until his death. He was also Count of Burgundy from 1208 to 1231, by his marriage to Countess Beatrice II, and Margrave of Istria and Carniola from 1228 until his death.

The House of Andechs was a feudal line of German princes in the 12th and 13th centuries. The counts of Dießen-Andechs obtained territories in northern Dalmatia on the Adriatic seacoast, where they became Margraves of Istria and ultimately dukes of a short-lived imperial state named Merania from 1180 to 1248. They were also self-styled lords of Carniola.