Where did dairy cows come from?

The six common breeds of dairy cows found in the United States originated from the following locations:
Ayrshire – County Ayrshire (Scotland)
Brown Swiss – Switzerland
Guernsey – Isle of Guernsey (English Channel)
Jersey – Isle of Jersey (English Channel)
Holstein – Province of Friesland (Netherlands or Holland) or State of Holstein (Germany)
Milking Shorthorn – Northeastern England