Kelthos in 2269.

Kelthos was a male Klingon who, sometime prior to 2269, became lost and trapped within the spatial anomaly within the Delta Triangle. There, he encountered the people of Elysia, and eventually became a member of the Elysian Council. Though he embraced the peaceful philosophies of Elysia, he still retained a degree of arrogance, particularly toward his Romulan colleague, Xerius, as well as toward Humans. (SCE eBook: Where Time Stands Still)
A Klingon councilor was depicted in the TAS episode "The Time Trap", but he was given no name or dialogue. From his unridged appearance, it can be assumed his ship was lost sometime after the spread of the Qu'Vat virus in 2154.
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