The Lisbon earthquake and fire took place on November 1, 1755. As many as 30,000 people were killed and the city reduced to ruins. This was the crucial event that led Voltaire to make his two strongest attacks on philosophical optimism, in Poème sur le désastre de Lisbonne, written shortly after the disaster occurred, and in Candide.
Voltaire achieved one of his several climaxes in the story when he had his young hero bewail the fact that he had to witness the hanging of his "dear Pangloss" and the drowning of his "dear Anabaptist, best of men," and to learn that the pearl of young ladies, Madamoiselle Cunégonde, had been disemboweled — all without learning the necessary cause thereof.
