Wolf pups were stolen and tamed and domesticated by the Native Americans to help them to hunt. The first tribe that did wasn't sited. The wolfs were the first dog, technically. All we really know is that they domesticated them, and not where it first started.
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Considering the fact that people had domestic dogs in the Americas and Australia, it seems to me that the first dogs were domesticated in Eurasia before humans spread to the Americas and Australia.
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Dogs were not "discovered." They were bred from wolves about 10 to 15 thousand years ago.
See http://www.dog-names.org.uk/history-evolution-dogs.htm
The first dog was discovered from a wolf. God thought that it should not be called a wolf so he rewarded it to be God's name backwards. DOG.