The famous ruler of Wayanad who fought against colonial powers was Pazhassi Raja. He is well known for his guerilla warfare against the British, particularly resisting their attempts to take control over Wayanad, which was traditionally part of the Kottayam kingdom. Pazhassi Raja's struggle continued fiercely until his death in the early 19th century. It is worth noting that the ruler who fought against the Dutch in this region was Marthanda Varma, the king of Travancore, who defeated the Dutch at the Battle of Colachel in 1741. However, Marthanda Varma's conflict was primarily centered around Travancore, not Wayanad. The resistance in Wayanad itself against colonial powers was led by Pazhassi Raja, who fought mainly against the British. In summary:

• Marthanda Varma fought and defeated the Dutch in the Travancore area.
• Pazhassi Raja was the famous ruler of Wayanad known for fighting against the British colonial forces.

Hence, the famous ruler of Wayanad who fought against colonial powers (British) was Pazhassi Raja. The famous ruler associated with fighting the Dutch in the region was Marthanda Varma of Travancore.