1755 Lisbon earthquake


The 1755 Lisbon earthquake, also known as the Great Lisbon earthquake, occurred in Portugal on the morning of Saturday, 1 November, Feast of All Saints, at around 09:40 local time. In combination with subsequent fires and a tsunami, the earthquake almost totally destroyed Lisbon and adjoining areas. Seismologists today estimate the Lisbon earthquake had a magnitude of 8.4 on the moment magnitude scale, with its epicenter in the Atlantic Ocean about west-southwest of Cape St. Vincent. Chronologically it was the third known large scale earthquake to hit the city. Estimates place the death toll in Lisbon alone between 10,000 and 30,000 people, making it one of the deadliest earthquakes in history.
The earthquake accentuated political tensions in Portugal and profoundly disrupted the country's colonial ambitions. The event was widely discussed and dwelt upon by European Enlightenment philosophers, and inspired major developments in theodicy. As the first earthquake studied scientifically for its effects over a large area, it led to the birth of modern seismology and earthquake engineering.

Earthquake and tsunami

The earthquake struck on the morning of 1 November 1755, All Saints' Day. Contemporary reports state that the earthquake lasted between three and a half and six minutes, causing fissures wide in the city center. Survivors rushed to the open space of the docks for safety and watched as the sea receded, revealing a plain of mud littered with lost cargo and shipwrecks. Approximately 40 minutes after the earthquake, a tsunami engulfed the harbor and downtown area, rushing up the Tagus river "so fast that several people riding on horseback ... were forced to gallop as fast as possible to the upper grounds for fear of being carried away." It was followed by two more waves. Candles lit in homes and churches all around the city for All Saints' Day were knocked over, starting a fire that developed into a firestorm which burned for hours in the city, asphyxiating people up to from the blaze.
Lisbon was not the only Portuguese city affected by the catastrophe. Throughout the south of the country, in particular the Algarve, destruction was rampant. The tsunami destroyed some coastal fortresses in the Algarve and, in the lower levels, it razed several houses. Almost all the coastal towns and villages of the Algarve were heavily damaged, except Faro, which was protected by the sandy banks of Ria Formosa. In Lagos, the waves reached the top of the city walls. Other towns of different Portuguese regions, such as Peniche, Cascais, and even Covilhã, which is located near the Serra da Estrela mountain range in central inland Portugal, were affected. The shock waves of the earthquake destroyed part of Covilhã's castle walls and its large towers. On the island of Madeira, Funchal and many smaller settlements suffered significant damage. Almost all of the ports in the Azores archipelago suffered most of their destruction from the tsunami, with the sea penetrating about inland. Portuguese towns in northern Africa were also affected by the earthquake, such as Ceuta and Mazagon, where the tsunami hit hard the coastal fortifications of both towns, in some cases going over it, and flooding the harbor area. In Spain, the tsunamis swept the Andalusian Atlantic Coast, nearly destroying the city of Cadiz, killing at least 1/3 of its population.
Shocks from the earthquake were felt throughout Europe as far as Finland and North Africa, and according to some sources even in Greenland, and the Caribbean. Tsunamis as tall as swept the coast of North Africa, and struck Martinique and Barbados across the Atlantic. A tsunami hit Cornwall on the southern British coast. Galway, on the west coast of Ireland, was also hit, resulting in partial destruction of the "Spanish Arch" section of the city wall. In County Clare there was the creation of Aughinish Island when a low lying connection to the mainland was washed away. At Kinsale, several vessels were whirled round in the harbor, and water poured into the marketplace.
In 2015, it was revealed that the tsunami waves may have reached the coast of Brazil, then a colony of Portugal. Letters sent by Brazilian authorities at the time of the earthquake describe damage and destruction caused by gigantic waves.
Although seismologists and geologists have always agreed that the epicenter was in the Atlantic to the West of the Iberian Peninsula, its exact location has been a subject of considerable debate. Early hypotheses had proposed the Gorringe Ridge until simulations showed that a source closer to the shore of Portugal was required to comply with the observed effects of the tsunami. A 1992 seismic reflection survey of the ocean floor along the Azores–Gibraltar Transform Fault detected a thrust fault southwest of Cape St. Vincent, with a dip-slip throw of more than. This structure may have created the primary tectonic event.

Casualties and damage

Economic historian Álvaro Pereira estimated that of Lisbon's population at the time, of approximately 200,000 people, some 30,000–40,000 were killed; another 10,000 may have lost their lives in Morocco. However, a 2009 study of contemporary reports relating to the 1 November event found them vague and difficult to separate from reports of another local series of earthquakes on 18–19 November. Pereira estimated the total death toll in Portugal, Spain and Morocco from the earthquake and the resulting fires and tsunami at 40,000 to 50,000 people.
Eighty-five percent of Lisbon's buildings were destroyed, including famous palaces and libraries, as well as most examples of Portugal's distinctive 16th-century Manueline architecture. Several buildings that had suffered little earthquake damage were destroyed by the subsequent fire. The new Lisbon opera house, opened just six months before, burned to the ground. The Royal Ribeira Palace, which stood just beside the Tagus river in the modern square of Terreiro do Paço, was destroyed by the earthquake and tsunami. Inside, the 70,000-volume royal library as well as hundreds of works of art, including paintings by Titian, Rubens, and Correggio, were lost. The royal archives disappeared together with detailed historical records of explorations by Vasco da Gama and other early navigators. The palace of Henrique de Meneses, 3rd Marquis of Louriçal, which housed an invaluable library of 18,000 books, was also destroyed. The earthquake damaged several major churches in Lisbon, namely the Lisbon Cathedral, the Basilicas of São Paulo, Santa Catarina, São Vicente de Fora, and the Misericórdia Church. The Royal Hospital of All Saints in the Rossio square was consumed by fire and hundreds of patients burned to death. The tomb of national hero Nuno Álvares Pereira was also lost. Visitors to Lisbon may still walk the ruins of the Carmo Convent, which were preserved to remind Lisboners of the destruction.

Relief and reconstruction efforts

The royal family escaped unharmed from the catastrophe: King Joseph I of Portugal and the court had left the city, after attending mass at sunrise, fulfilling the wish of one of the king's daughters to spend the holiday away from Lisbon. After the catastrophe, Joseph I developed a fear of living within walls, and the court was accommodated in a huge complex of tents and pavilions in the hills of Ajuda, then on the outskirts of Lisbon. The king's claustrophobia never waned, and it was only after Joseph's death that his daughter Maria I of Portugal began building the royal Ajuda Palace, which still stands on the site of the old tented camp. Like the king, the prime minister Sebastião de Melo survived the earthquake. When asked what was to be done, Pombal reportedly replied "Bury the dead and heal the living", and set about organizing relief and rehabilitation efforts. Firefighters were sent to extinguish the raging flames, and teams of workers and ordinary citizens were ordered to remove the thousands of corpses before disease could spread. Contrary to custom and against the wishes of the Church, many corpses were loaded onto barges and buried at sea beyond the mouth of the Tagus. To prevent disorder in the ruined city, the Portuguese Army was deployed and gallows were constructed at high points around the city to deter looters; more than thirty people were publicly executed. The army prevented many able-bodied citizens from fleeing, pressing them into relief and reconstruction work.
The Project for the Royal Palace in Campo de Ourique was proposed as the new royal residence in 1760, but the plans were later abandoned due to a lack of priority or interest in a palace being built in the Campo de Ourique neighborhood of Lisbon.
The king and the prime minister immediately launched efforts to rebuild the city. On 4 December 1755, little more than a month after the earthquake, Manuel da Maia, chief engineer to the realm, presented his plans for the re-building of Lisbon. Maia presented four options from abandoning Lisbon to building a completely new city. The first plan was to rebuild the old city using re-cycled materials; this was the cheapest option. The second and third plans proposed widening certain streets. The fourth option boldly proposed razing the entire Baixa quarter and "laying out new streets without restraint". This last option was chosen by the king and his minister.

In less than a year, the city was cleared of debris. Keen to have a new and perfectly ordered city, the king commissioned the construction of big squares, rectilinear, large avenues and widened streetsthe new mottos of Lisbon.
The Pombaline buildings are among the earliest seismically protected constructions in Europe. Small wooden models were built for testing, and earthquakes were simulated by marching troops around them. Lisbon's "new" Lower Town, known today as the Pombaline Lower Town, is one of the city's famed attractions. Sections of other Portuguese cities, such as the Vila Real de Santo António in Algarve, were also rebuilt along Pombaline principles.
The Casa Pia, a Portuguese institution founded by Maria I, and organized by Police Intendant Pina Manique in 1780, was founded following the social disarray of the 1755 Lisbon earthquake.

Effect on society, economy and philosophy

The earthquake had wide-ranging effects on the lives of the populace and intelligentsia. The earthquake had struck on an important religious holiday and had destroyed almost every important church in the city, causing anxiety and confusion amongst the citizens of a staunch and devout Roman Catholic country. Theologians and philosophers focused and speculated on the religious cause and message, seeing the earthquake as a manifestation of divine judgment.

Economy

A 2009 study estimated that the earthquake cost between 32 and 48 percent of Portugal's GDP. Also, "in spite of strict controls, prices and wages remained volatile in the years after the tragedy. The recovery from the earthquake also led to a rise in the wage premium of construction workers. More significantly, the earthquake became an opportunity to reform the economy and to reduce the economic semi-dependency vis-à-vis Britain."

Philosophy

The earthquake and its aftermath strongly influenced the intelligentsia of the European Age of Enlightenment. The noted writer-philosopher Voltaire used the earthquake in Candide and in his Poème sur le désastre de Lisbonne. Voltaire's Candide attacks the notion that all is for the best in this, "the best of all possible worlds", a world closely supervised by a benevolent deity. The Lisbon disaster provided a counterexample. As Theodor Adorno wrote, "he earthquake of Lisbon sufficed to cure Voltaire of the theodicy of Leibniz". Jean-Jacques Rousseau was also influenced by the devastation following the earthquake, whose severity he believed was due to too many people living within the close quarters of the city. Rousseau used the earthquake as an argument against cities as part of his desire for a more naturalistic way of life.
Immanuel Kant published three separate texts on the Lisbon earthquake. As a younger man, fascinated with the earthquake, he collected all the information available in news pamphlets and formulated a theory of the causes of earthquakes. Kant's theory, which involved shifts in huge caverns filled with hot gases, was incorrect, but was one of the first systematic attempts to explain earthquakes in natural rather than supernatural terms. According to Walter Benjamin, Kant's slim early book on the earthquake "probably represents the beginnings of scientific geography in Germany. And certainly the beginnings of seismology".
Werner Hamacher has claimed that the earthquake's consequences extended into the vocabulary of philosophy, making the common metaphor of firm "grounding" for philosophers' arguments shaky and uncertain: "Under the impression exerted by the Lisbon earthquake, which touched the European mind in one its more sensitive epochs, the metaphor of ground and tremor completely lost their apparent innocence; they were no longer merely figures of speech". Hamacher claims that the foundational certainty of René Descartes' philosophy began to shake following the Lisbon earthquake.

Politics

The earthquake had a major impact on politics. The prime minister, Sebastião José de Carvalho e Melo, 1st Marquis of Pombal, was the favorite of the king, but the aristocracy despised him as an upstart son of a country squire. The prime minister, in turn, disliked the old nobles, whom he considered corrupt and incapable of practical action. Before 1 November 1755 there was a constant struggle for power and royal favor, but the competent response of the Marquis of Pombal effectively severed the power of the old aristocratic factions. However, silent opposition and resentment of King Joseph I began to rise, which would culminate with the attempted assassination of the king in 1758 and the subsequent elimination of the powerful Duke of Aveiro and the Távora family.

Development of seismology

The prime minister's response was not limited to the practicalities of reconstruction. He ordered a query sent to all parishes of the country regarding the earthquake and its effects. Questions included:
The answers to these and other questions are still archived in the Torre do Tombo, the national historical archive. Studying and cross-referencing the priests' accounts, modern scientists were able to reconstruct the event from a scientific perspective. Without the questionnaire designed by the Marquis of Pombal, this would have been impossible. Because the marquis was the first to attempt an objective scientific description of the broad causes and consequences of an earthquake, he is regarded as a forerunner of modern seismological scientists.

In popular culture

A fictionalized version of the 1755 Lisbon earthquake features as a main plot element of the 2014 video game Assassin's Creed Rogue, developed and published by Ubisoft. Notably, a similar earthquake occurs earlier in the story in Port-au-Prince, Haiti, and possibly coincides with a real-world earthquake recorded there in 1751.
The album 1755 by the Portuguese Gothic Metal band Moonspell is a concept album detailing the story of the 1755 Lisbon earthquake. The album is entirely sung in Portuguese and explores not only the history but also its effects on Portuguese society, culture and spirituality.
The disaster is the inspiration for the board game where the events of the 22-year restoration project are simulated.