A very long time ago (the Middle ages to be precise) there existed the nomadic tribe of Tartar who inhabited central Asia and eastern Europe. The Tartars would move from place to place, and keep their beef under their saddles. The galloping horses would crush and grind the meat as well as tenderize it. The Tartars could cook this easily given the limited facilities while traveling, or eat raw when circumstances did not favor cooking.
A German merchant visiting Asia observed this, and took the idea home with him to his hometown of Hamburg. The meat was mixed with local spices, fried or broiled, and then presented to people as “Hamburg” steak. German emigrants to the USA took the Hamburg steak with them, and presented the cookery to the Americans. It gained popularity – the first mention in print of