This is my specialty. Cows and cattle have been a part of my life since before I can remember, and it reflects in how this topic is something I am very knowledgeable in. No one really knows, because it was unrecorded in the history books of who really figured out how to milk a cow. Cows have been around and domesticated for thousands of years, so all we know, the Egyptian's could've been the first ones to found that milk from a cow was just as good to drink as a big cup of water!