When the Earth Trembled: Recounting the 1755 Lisbon Earthquake

If you are a history buff and are interested in diving into events that forever changed the course of a city, then learning about the 1755 earthquake in Lisbon is the way to go. This seismic event stands as a crucial turning point in the city's history, forever altering its landscape and leaving a profound mark on its inhabitants. In this blog post, we will try to walk you through the main events and the aftermath.

The earthquake: How it happened

In the early morning of November 1, 1755, the city of Lisbon awoke to an unimaginable horror. At 9:40 a.m., the ground beneath the city began to shake aggressively, marking the beginning of one of the most devastating earthquakes in European history. The earthquake is estimated to have a magnitude ranging from 8.5 to 9 on the Ritcher scale. The epicenter for the earthquake was 320 km to the southwest of Lisbon, in the middle of the Atlantic Ocean. To make matters worse, the fact that November 1 is the day of “All Saints” and Portugal is a deeply religious country, so most people were in packed churches celebrating. The medieval churches were not designed to withstand the violent movements caused by the earthquake, and many people died as the roofs of the churches collapsed. Furthermore, for religious celebrations, every candle in the churches was lit, and there were a lot of flammable decorations which led to many fires that ravaged Lisbon for 5 days.

Unfortunately, the earthquake wasn’t the only disaster Lisbon experienced. A massive tsunami, generated by the seismic disturbance, surged toward the coastline. Many people after the earthquake had fled to the safety of the open docks unaware of what was about to happen. The combination of these calamities proved to be deadly. Tens of thousands of lives were tragically lost, and countless others were injured or displaced. The destruction was so extensive that it extended beyond the city limits, impacting neighboring towns and villages as well. The higher areas of Lisbon were also not safe as the fires kept spreading. As the dust settled and the city lay in ruins, the survivors emerged from the rubble, grappling with the magnitude of the catastrophe. A week after the earthquake over 90% of the buildings in Lisbon had collapsed due to the earthquakes, the tsunamis, and the fires. The heartache and loss were immeasurable, and the process of recovery seemed almost impossible.

The Marquis of Pombal: How to reconstruct a city

The prime minister at the time of the disasters was Sebastião de Melo, known as Marquis of Pombal. He was responsible for restoring the city from the bricks, and he proved to be a visionary leader, forever changing the landscape of the city. As the Prime Minister and Secretary of State for Internal Affairs of Portugal at the time, the Marquis of Pombal wasted no time in taking decisive action. When he was asked what to do immediately after he replied, “Bury the dead and heal the living”. Recognizing the need for swift and efficient measures, he implemented a comprehensive plan for the reconstruction of Lisbon, employing innovative approaches and forward-thinking strategies. He overruled the church and prevented the spread of diseases by ordering the dead to be taken into damaged ships and burning the bodies out of the sea

One of the Marquis' priorities was to address the immediate needs of the survivors and provide relief to those affected by the earthquake. He organized rescue efforts, established emergency shelters, and coordinated the distribution of essential supplies. By displaying compassion and leadership during this critical time, the Marquis instilled a sense of hope and resilience in the city's inhabitants. However, the Marquis of Pombal's leadership extended far beyond the immediate aftermath of the disaster. He didn’t neglect the importance of urban planning and the necessity of building a more resilient city for the future. He introduced groundbreaking measures to ensure the safety and stability of the rebuilt Lisbon.

The Marquis implemented strict building codes and regulations that are still used to this day, mandating the use of stronger materials and earthquake-resistant construction techniques. He gathered the expertise of engineers and architects, encouraging innovative designs that could be more prepared for future events. Under his guidance, a new Lisbon began to emerge that can be seen to this day, characterized by wide streets, open squares, and buildings designed with both aesthetics and functionality in mind. Besides leading the physical reconstruction, the Marquis of Pombal also implemented significant political and social reforms. He modernized the administration of the city, simplifying bureaucracy, and centralizing power. His policies aimed to promote economic growth, stimulate trade, and revive the city's commercial activities. With a focus on education, he founded the Royal Academy of Sciences and implemented educational reforms to foster intellectual and cultural development.

Architectural changes:

With the rebuilding of Lisbon, the architectural practices changed in multiple ways. Lisbon was a typical medieval city, full of small and crooked streets and alleys. Marquis de Pombal led the change for a different Lisbon. There was the implementation of a new urban design for the city center known as Baixa Pombalina. They constructed linear and wide streets that were paved with the famous “calçada portuguesa”. Furthermore, the facades of the newly constructed buildings had to follow certain guidelines. The newly founded style was labeled as Pombaline style, and these are some ways you can recognize it when you see a building/house in Lisbon:

1. The facades, normally with 3 bays:                                  

2. In the roofs, pay attention to the small windows that are there:

3. The iron balconies:

4. Wooden Beams:

Besides Baixa Pombalina, other areas of Lisbon also experienced architectural changes. The famous Alfama neighborhood, for instance, underwent significant reconstruction after the earthquake. While preserving its historical character, the buildings were reinforced and were more resilient to seismic events. Today, Alfama still showcases the traditional narrow streets and traditional architecture, but with strengthened structures. In general, there was a greater effort to use more durable materials, such as stone, brick, and reinforced concrete, which became more prevalent. Buildings were designed with stronger foundations, thicker walls, and improved structural systems to withstand future seismic events.  The rebuilding process was based on other architectural styles prevalent at the time. Neoclassical influences were incorporated into the design of many new buildings, incorporating elements such as grand facades, columns, and ornamental detailing.

Another prominent location you will surely come across in Lisbon that is linked to the earthquake and Marquis of Pombal is the Praça do Marquês de Pombal. Located at the top of Avenida da Liberdade, it serves as a significant tribute to the Marquis of Pombal and his instrumental role in rebuilding the city. The square features an iconic monument dedicated to the Marquis, designed by the sculptor Francisco dos Santos. The monument stands as a symbol of Lisbon's resilience and the visionary leadership of the Marquis during the difficult reconstruction process. Another notable sight that emerged from the earthquake is the Águas Livres Aqueduct. This monumental structure, constructed in the 18th century, served as a vital water supply system for the city. It showcases impressive engineering feats and architectural grandeur, stretching across the Alcântara Valley with its series of arches.

The Birth of Seismology: Scientific Advances Arise

The Great Lisbon Earthquake of 1755 not only left a lasting impact on the physical landscape of the city but also was a stepping stone for a scientific revolution that would help us understand earthquakes better. This catastrophe catalyzed the birth of seismology, a field dedicated to the study of everything related to earthquakes. In the wake of the disaster, scientific advances arose, creating a new era of knowledge and exploration. Before the Great Lisbon Earthquake, the nature and origins of seismic events were not well understood. However, in the aftermath of the catastrophe, a newfound curiosity and urgency arose among scholars, scientists, and philosophers to truly understand the secrets of the phenomenon.

One of the most important figures in the field was the Portuguese scientist Alexandre Rodrigues Ferreira. Recognizing the need for comprehensive and accurate data, Ferreira started an ambitious mission to document the earthquake's effects throughout Portugal. He gathered information on the seismic intensity, ground shaking, and damage caused by the earthquake, laying the groundwork for future scientific investigations. Another crucial development came in the form of the invention of the seismograph. This instrument, capable of measuring and recording seismic activity, revolutionized the study of earthquakes. It enabled scientists to quantify the magnitude and duration of ground shaking, providing invaluable insights into the behavior of seismic waves and their propagation. One of the most influential seismographs of the time was designed by John Michell, an English clergyman and natural philosopher. His device, known as the "earthquake machine," utilized a pendulum and a stylus that recorded the movement on a rotating drum. This innovation allowed for the precise measurement and analysis of seismic waves.

Quake (Lisbon earthquake experience)

If you like interactive museums, Quake is a great option to learn more about the 1755 Lisbon Earthquake.  The museum aims to educate visitors about the historical event and its consequences through interactive exhibits, multimedia presentations, and engaging displays.

At Quake, visitors can explore different aspects of the earthquake, including its causes, the destruction it caused, and the subsequent reconstruction efforts. The museum uses advanced technology and interactive installations to create a captivating and educational experience. You will find simulations, audiovisual presentations, and informative displays that showcase the earthquake's impact on Lisbon's architecture, society, and culture. Prices are 21 per person in groups of less than 10, and 19 if your group has more than 10 people. The museum is located in Belém.

Lessons Learned:

This devastating event led to a series of important discoveries that made us more prepared for future situations that may arise. These were the main lessons learned:

Seismic-resistant Design: The destruction caused by the earthquake highlighted the importance of designing structures that were more prepared in case of a similar event. Architects and engineers began to incorporate seismic-resistant techniques into their designs, such as flexible building materials, reinforced foundations, and shock-absorbing structures. By distributing and dissipating seismic energy, these measures help to minimize the impact of earthquakes and increase the safety of inhabitants.

Urban Planning: The devastation in Lisbon revealed the vulnerabilities of dense urban environments during a seismic event. Planners recognized the need for open spaces, wider streets, and strategically located public squares to provide escape routes and gathering spaces in times of crisis. Urban layouts were reimagined to prioritize safety, accessibility, and the efficient flow of traffic during emergencies.

Building Codes and Regulations: In response to the earthquake, stricter building codes and regulations were established to ensure the safety of future constructions. These guidelines involved the use of robust materials, proper structural reinforcement, and compliance with specific construction practices. Regular inspections and certifications became commonplace, ensuring that buildings met the necessary safety standards.

Preservation of Historic Heritage: Perhaps not so obvious, but a key lesson learned in the aftermath, was the importance of preserving important monuments and buildings. Restoration efforts were initiated to revive damaged structures and preserve their historical and cultural significance, while also integrating modern safety measures to ensure their long-term stability

To summarize, the 1755 earthquake was a turning point in Lisbon’s history. The consequences were devastating and many lives were lost, and this sparked a scientific revolution. Architectural practices were revolutionized and urban planning strategies changed. The lessons learned from this devastating event continue to guide us in building resilient cities, preserving cultural heritage, and prioritizing safety. As we reflect on Lisbon's remarkable journey of recovery and transformation, we are reminded of the importance of learning from the past to create a better, more resilient future.