What is French dressing?
The universal vinegar and oil in the ratio 1:3, often by spicy mustard or blue cheese. The notion of elegant simplicity influenced American gourmets late 19th Century
In England, is often the classic vinaigrette so named in the U.S. was the basic idea further etwickelt and composition with creamy mayonnaise and ketchup increased. The states in the Old World American dressing, was rather unknown in America.