Which ancient breed was used by Vikings and is now popular as a driving animal, characterized by its dun coloring?

The Norwegian Fjord is indeed a breed with strong historical connections to the Vikings. Originating from Norway, this breed is known for its distinct dun coloring, which can range from a light beige to a darker brown, often with a characteristic dorsal stripe and zebra-like coloration on its legs.

This breed's robust build and calm demeanor make it well-suited for a variety of work, including driving, which contributes to its current popularity in equestrian activities. The Norwegian Fjord's versatility, physical strength, and gentle nature allow it to excel in driving tasks, making it a favored choice among enthusiasts who appreciate its combination of historical significance and practical abilities.

Its link to Viking culture underscores its heritage, as it was historically used for farming, transportation, and warfare. The Icelandic horse, while also a strong breed related to Vikings, does not share the same widespread use in driving activities. The Morgan and Gotland breeds, while notable in their own rights, do not have the same direct association with the characteristics and historical use mentioned in the question.