Consumption.

The Commercial Revolution that began in Europe around 1000 C.E. rested on a firm foundation of cloth and clothing production. As Europe's cities increased in population during the High Middle Ages, fabric weaving became a lucrative business, and by the early Renaissance Italy was Europe's preeminent center of cloth production, exporting fine silks and woolens throughout the continent. The production of cloth—an item for which there was universal need—was the foundation upon which great Renaissance economies relied, and the spinning of fabric produced much of the enormous wealth that allowed the era's elites to indulge their tastes for art, fine buildings, and sumptuous fashions. The guilds that controlled the milling of wool and the weaving of textiles were usually the most important commercial organizations in Europe's cities, and they often dominated local politics. In Florence, perhaps as many as...