In the seventeenth century, Amsterdam and London developed distinctive innovations in finance through both banks and markets that facilitated the growth of trade in each city. In the eighteenth century, a symbiotic relation developed that led to bank-oriented finance in Amsterdam cooperating with market-oriented finance in London. The relationship that emerged allowed each to rise to unprecedented dominance in Europe, while the respective financial innovations in each city provided the means for the continued expansion of European trade, both within Europe and with the rest of the world. The increasing strains of war finance for the competing European powers over the course of the eighteenth century stimulated fresh financial innovations in each city that initially reinforced the symbiosis of the two centers. The external shocks arising from revolutionary movements in America and France, however, interrupted the relationship long enough to leave London as the supreme financial center.