The Dog Soldier is the unique unit of the Native American civilization.
Strategy[]
Compared to the Axeman, which the Dog Soldier replaces, the Dog Soldier has 1 less strength, but twice as much bonus against Melee Units, and can be built without any resources.
Using Dog Soldiers[]
Against other melee units, the Dog Soldier can be considered to have a strength of 8, rather than the Axeman's 7.5, however any skills on Dog Soldiers are less effective than on normal axes, so a Shock Axe is on roughly equal footing to a Dog Soldier and any other bonuses are much more effective on Axes (e.g., a Dog Soldier has trouble attacking an Axe if it's on defensive terrain).
The Dog Soldier is also very effective for early-game rushes. With no need to spend time building a Copper Mine for resources, a quick army can be formed to conquer opponents who may not have even reached Archery. Try promoting them in Woodsman promotions, so they can get to enemies quickly.
Against Dog Soldiers[]
As such an effective rushing unit, if you see the Native Americans near you, it may be best to rush to Archery before anything else (other than maybe Religion.) Dog Soldiers are weaker against Archers than normal Axemen, and even more prone to Chariots.
Civilopedia entry[]
The Dog Soldiers were the elite of the Cheyenne warriors and some of the most feared fighters in the American West. Members of a prestigious fraternal society, the Dog Soldiers each received a "Dog Sash" upon entrance into the group. While at first merely emblems of membership, the "Dog Sash" soon became a symbol of iron will in combat. This reputation stemmed from the Dog Soldier habit of, during particularly brutal combat, staking themselves to the ground by way of their "Dog Sash" and not moving from the spot until victory or death had overtaken them.