The Lisbon earthquake, which occurred on the morning of November 1, 1755, was one of the most severe and significant natural disasters in Western European history. The event consisted of two large tremors and a resulting tidal wave that hit Lisbon shortly afterward. Though there is no way of knowing how strong the earthquake was, between 20,000 and 60,000 people were estimated dead (about 8-20% of the current population of Lisbon) and aftershocks were said to have been felt as far away as Finland.

When the earthquake occurred, Europe was in the midst of the Age of Enlightenment, a cultural movement defined by a belief in reason, rationality, and sensory evidence. Some of the European intelligentsia, as a result, began to express doubt about systems of knowing (epistemologies) that were not founded in reason or material evidence. “The Lisbon Earthquake” makes direct reference to this when the speaker states “To nature we apply for truth in vain” (Line 181). True to Enlightenment values, Voltaire’s poem is, at times, hyper-focused on finding some logical reasoning in the disaster’s devastation. Reason, after all, was seen as an essential measure of truth—so much so that Voltaire’s speaker, in the poem, expects God to answer to it.