The magnificent art and new ways of thinking in the Renaissance rested on economic and political developments in the city-states of northern Italy. Economic growth laid the material basis for the Italian Renaissance, and ambitious merchants gained political power to match their economic power. They then used their money and power to buy luxuries and hire talent in a system of patronage, through which cities, groups, and individuals commissioned writers and artists to produce specific works. Political leaders in Italian cities admired the traditions and power of ancient Rome, and this esteem shaped their commissions. Thus economics, politics, and culture were interconnected.