Why was the renaissance able to flourish in northern italy

The main reason why the Renaissance was able to flourish in northern Italy is because this was a particularly wealthy area--meaning that patrons of the arts could spend money on artistic luxuries in ways other people in other territories could not. 

One factor that enabled the Renaissance to flourish in Northern Italy was that the region had a wealthy class that invested in the arts. Wealthy families, such as the Medici, in Northern Italy invested in the arts and hired world-class artists such as Michelangelo and Botticelli, thus encouraging the movement toward individual expression embodied by Humanism.

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