Ottokar I, Count of Steyr (died 1064), was the founder of the dynasty of the Otakars. From 1056 to 1064, he was margrave of the Karantanian March, later to be known as Styria (named Steiermark in German after the town of Steyr, where Ottokar was count). The margraves Adalbero and Ottokar II were his sons. He ended the war against Hungary.

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Adalbero |}