There must be a reason why the Americans of USA are called Yanks/Yankees. The word actually has no relation with the animal Yak, which some think has something to do with this. The word was coined by English pirates in reference to the Dutch, who were known pretty much for their diet of cheese only. Which in their language is Kaas, a christian name such as Jan tied with this would become Jan Kass, pronounced (Yan-Kas). So it could be that’s how the English called the Dutch who had settled in New York. However it could be the other theory, the one about the native Indians, they use to call the English, Yengees that’s how they pronounced the French word of English, Anglais.
Did you know that New York was formerly called New Amsterdam and it was also the capital of New Netherlands. That is why there are many historical buildings with a dutch architecture.