Centuries ago Venice was major world power: trading routes & influence throughout the world. Got notice plague coming, but to preserve commerce opted to do nothing. 1/3 of city died in ensuing outbreak, at all levels of society. Without people, functions of society ground to a halt & trade became untenable. Other European powers replaced them, their trading outposts & influence. They never recovered their wealth or power, declining into the museum city they are now.
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