France, 1834-1910
He revolutionized economics with his rigorous mathematical formulation of the mechanics of the price system.
England, 1842-1924
He demonstrated the tremendous theoretical power of demand and supply curves, and bequeathed to economics the critical distinction between the short run and the long run.
United States, 1857-1929
One of the leading Institutionalists, he is best remembered for his theory of "conspicuous consumption" which parodied the ostentation of the Gilded Age.