Latest / The History of Portugal: The Small Nation That Built a Global Empire — Fexingo History / The Lisbon Earthquake of 1755 and the Birth of Modern Seismology
Transcript
- Lucas: Today we're talking about a single day that reshaped Portugal forever — and in a way, the whole Western world. November 1st, 1755. All Saints' Day. Lisbon was packed with people attending Mass, candles lit in churches across the city. Luna: Oh I remember reading about this — the Lisbon earthquake. One of the deadliest in history, right? Lucas: Exactly. Around 9:30 in the morning, the ground began to shake. Three distinct shocks, each one stronger than the last. The third one was catastrophic — it brought down most of Lisbon's churches, palaces, and homes. The city had been built on unstable ground, on sand and alluvial soil, so the buildings just collapsed. Lucas: But the earthquake itself was only the beginning. Because the epicenter was offshore in the Atlantic, it triggered a massive tsunami. About forty minutes after the shaking stopped, a wall of water — estimates range from 12 to 18 meters high — slammed into the harbor and surged up the Tagus River. It washed away the crowded quays and the ships anchored there. Luna: And on top of all that, there were fires. Lucas: Yes. The candles from the churches and homes that collapsed started fires everywhere. The fires burned for days, completing the destruction. All told, in Lisbon alone, somewhere between 10,000 and 40,000 people died — we don't have exact numbers. But the city was almost entirely leveled. Luna: So it was a triple disaster — earthquake, tsunami, fire. How did the government react? King José I was on the throne then, right? Lucas: King José I was terrified of earthquakes after that experience — he actually refused to live inside stone buildings for the rest of his life. But the real man of the hour was his Secretary of State, Sebastião José de Carvalho e Melo — better known today as the Marquês de Pombal. He was the one who took charge of the response. Lucas: Pombal's first move was brutally pragmatic. He ordered the army to cordon off the city and prevent looting. Then he famously said, 'Bury the dead and feed the living.' Within days, he organized mass burials at sea to prevent disease, set up temporary shelters, and began issuing emergency rations. Lucas: But his most lasting achievement was the reconstruction. He oversaw the creation of an entirely new city plan for the central district — the Baixa Pombalina. It was one of the first examples of modern urban planning, with wide, straight streets, standardized building heights, and a grid layout designed to be earthquake-resistant. Luna: Wait — earthquake-resistant? In the 18th century? Lucas: Yes. The new buildings were constructed with a flexible wooden frame called 'gaiola' — a cage-like structure that could sway with the tremors rather than collapse. The walls were made of masonry, but they were built over that wooden skeleton. And the streets were designed wide enough to serve as firebreaks. It was revolutionary. Luna: That's incredible. So Pombal didn't just rebuild — he basically reinvented the city. Lucas: Exactly. And he used the disaster as a political opportunity. He blamed the earthquake on the nobility and the Inquisition, accusing them of hindering progress. He marginalized the old aristocracy and centralized power under the crown. He also expelled the Jesuits from Portugal in 1759, partly because they opposed his reforms. Lucas: But the earthquake also had a huge intellectual impact across Europe. The event shook the confidence of the Enlightenment. Voltaire wrote a poem about the disaster, and later satirized the idea that 'all is for the best' in his novel Candide. Rousseau disagreed, arguing that the tragedy was made worse by human choices — building cities too densely, ignoring natural risks. Luna: And Kant even wrote about it, didn't he? Early seismology? Lucas: Yes! Immanuel Kant, just a few years after the earthquake, wrote three essays trying to explain it scientifically. He theorized about underground caverns and gases — wrong, but it was one of the first systematic attempts to study earthquakes as natural phenomena, not divine punishment. The Lisbon earthquake is often called the birth of modern seismology. Luna: It's amazing how one event could change so much — not just for Portugal but for the whole way people thought about the world. Lucas: It really did. And it's the kind of story we love to dig into on this show — the intersection of science, politics, and human resilience. If you've been stepping into history with us episode by episode, you know we put a lot of work into every conversation. And we're able to keep this show ad-free and independent thanks to listeners who support us at buy me a coffee dot com slash fexingo. Luna: Yeah, it's such a small way to help keep these stories alive. Every little bit goes straight into research and production. Lucas: So back to the reconstruction. Pombal also changed the social fabric. He abolished slavery in Portugal — though not in the colonies — and reformed the university system. He tried to modernize the economy, promoting manufacturing and breaking the power of the old merchant guilds. Lucas: The rebuilding of the Baixa took decades. But the core of his plan was completed by the 1770s. The Terreiro do Paço — the royal square in front of the palace — was redesigned as the Praça do Comércio, a grand commercial square open to the Tagus. It symbolized a new, outward-looking Portugal. Luna: And that square still stands today, right? It's one of the most famous landmarks in Lisbon. Lucas: It is. And if you walk through the Baixa Pombalina today, you're walking through a monument to 18th-century resilience and rationalism. The streets — like Rua Augusta, Rua da Prata, Rua dos Douradores — are laid out in a perfect grid. The buildings all look similar, because they were built to uniform designs. Lucas: But the reconstruction came at a cost. The Inquisition, though weakened, continued to try cases. And Pombal's authoritarian methods — his secret police, his censorship of the press — meant that the modern Lisbon was built on a foundation of state control as well as concrete and timber. Luna: There's always a trade-off, isn't there? Progress often comes with a darker side. Lucas: That's a theme we see over and over in Portuguese history. But the earthquake itself remains a powerful symbol. For the Portuguese, it's a reminder of both their vulnerability and their ability to rebuild. And for the world, it was a wake-up call that nature doesn't care about human plans — and that we have to learn to live with that uncertainty.