Hannibal's crossing of the Alps

Hannibal's crossing of the Alps in 218 BC was one of the major events of the Second Punic War, and one of the most celebrated achievements of any military force in ancient warfare.

Hannibal led his Carthaginian army over the Alps and into Italy to take the war directly to the Roman Republic, bypassing Roman and allied land garrisons, and Roman naval dominance.

The two primary sources for the event are Polybius and Livy. The Alps were not well-documented at the time, and no archaeological evidence is available, so all modern theories depend on interpreting the place names used by Polybius and Livy and comparing them with modern geographical knowledge.

A 2022 book by Dutch historian Jona Lendering suggests that the historical records about Hannibal's route are unclear and often disagree, making it very hard to know exactly how he crossed the mountains.

Background

After losing the First Punic War, Carthage wanted to recover and seek new lands to gain wealth. Hamilcar Barca led efforts to conquer Iberia, aiming to use it as a base to challenge Rome. He began this campaign in 238 BC, and over nine years, he took control of the southeastern part of Iberia.

After Hamilcar's death in 228 BC, his son-in-law Hasdrubal took command. However, in 221 BC, Hasdrubal was killed, and the army chose Hamilcar's 26-year-old son, Hannibal, as their new leader. Hannibal promised to continue his father's goal of conquering Iberia and then taking the war to Rome in Italy. In his first two years as commander, Hannibal worked to secure the lands his father had won and prepared for future battles.

Roman foreign relations

Hannibal knew a lot about Roman politics and saw that it was a good time to attack. He had spies from the Gallic people everywhere in the Roman Republic, even inside the Roman Senate. After the First Punic War, which ended in 241 BC, the Romans had been strengthening their control over Italy and also taking over places like Sicily, Corsica, and Sardinia.

The Romans had been fighting with the Padane Gauls, people from northern Italy, for over a hundred years. In 225 BC, these Gauls tried to attack Rome because they did not want Rome to take over their land, but they lost. By 224 BC, the Boii people had to agree to follow Roman rules, and soon after, so did the Anari. In 223 BC, the Romans fought again with the Insubres Gauls. After a tough battle, the Romans won and the Gauls were forced to obey Rome. In 222 BC, when the Gauls asked for peace, the Romans refused and defeated them in a big battle near Mediolanum. This made the Padane Gauls unhappy and ready to rebel again.

Preparations

Hannibal wanted to make sure he had a safe place to enter the Po valley after crossing the Alps. He sent messengers to the Gallic tribes living there. These tribes were unhappy with the Romans, who had taken their land and treated them badly. Two tribes, the Insubres and the Boii, were especially happy to help Hannibal.

Hannibal knew the Alps would be very hard to cross. He sent scouts to learn more about the mountains. The Gauls told him the descent would be steeper than the climb, so he wanted allies waiting for him at the bottom. Having friends in the area would make his journey safer.

Siege of Saguntum

Main article: Siege of Saguntum

Hannibal wanted the people of Saguntum to join him and start a war against Rome. He tried many tricks to make them attack first, but they only sent a message to the Romans about his actions. The Romans sent a group to try to make peace, but Hannibal ignored them, hoping they would declare war. The group saw that war was coming but said nothing. They told Rome that Hannibal was ready to act soon.

The Romans busy themselves with fighting in another place and did not help Saguntum, even though they had promised to. Hannibal surrounded Saguntum and began a long siege that lasted eight months. After capturing the city, Hannibal sold its people and took valuable items back to Carthage to gain support for his plans.

March through the Pyrenees

After spending the winter in Cartagena, Hannibal prepared his army for a tough campaign. He left his brother Hasdrubal in charge of protecting the area and swapped soldiers from Africa and Iberia to keep them loyal. Hannibal was worried the Romans might use Catalonia as a base, so he decided to conquer the region quickly. He split his army into three groups to take control of the area faster.

Hannibal’s army marched through many towns and faced several tribes, including the Illergetes. Though the campaign was quick, it was also very hard on his soldiers. After taking control, Hannibal left some troops behind to keep the area secure and sent others home to show support for his mission. His main group, which included important supplies and Hannibal himself, moved along the coast through several towns like Tarraco and Barcino. The other two groups moved through different valleys, making sure any resisting tribes were dealt with, and later joined up with the main group.

March to the Rhône

The journey to the Rhône River after crossing the Pyrenees was mostly calm for Hannibal's army, which had spent the previous July and August dealing with tribes in the Pyrenees. The lands they passed through had different feelings about the Carthaginians, the Romans, and Hannibal's army moving through.

The city of Massalia, now called Marseille, was a busy Greek trading place influenced by the Romans. Massalia was worried about Hannibal's army arriving and tried to get tribes on the east side of the Rhône River to support the Romans.

Publius Scipio, one of the leaders for 218 BC, was told by Roman leaders to stop Hannibal near the Ebro River or the Pyrenees. He was given 60 ships but moved slowly. When he reached the Po area, some local tribes began to rebel because they knew Hannibal was coming. Instead of using soldiers already prepared, Roman leaders decided to send new soldiers to the Po region and asked Publius Scipio to gather a new army. This was not done as quickly as needed. After organizing the new soldiers, Publius Scipio sailed from Ostia. Without compasses, ships sailed close to the coast and stopped each night. After sailing north along the Italian coast and then west, he stopped in Massalia. There, he learned that Hannibal was already north of the city, on the other side of the Rhône River.

Crossing the Rhône

Main article: Battle of Rhone Crossing

Hannibal’s march is often debated, especially his route over the Alps, but historians agree on where he camped near the Rhône River. The crossing was well planned and executed smoothly.

As Rome focused elsewhere, Hannibal used local tensions to his advantage. He persuaded nearby groups to help him gather boats and canoes for the crossing. While a group of Gauls waited on the far side to attack, Hannibal split his forces. One group crossed further north, then moved south to surprise the Gauls from behind. Meanwhile, Hannibal’s main force crossed openly, drawing attention away from the northern move. With both forces coordinated, the Gauls were caught off guard and quickly overcome, allowing Hannibal to cross the river successfully.

From the Rhône to the Alps

Hannibal needed to reach the Alps before winter arrived. He knew that if he waited until spring, the Romans would have more time to prepare their forces. He sent some of his soldiers to gather information about the Roman army near the Rhône River.

While his army was still gathering on one side of the river, Hannibal spoke to local leaders to gain their support. He wanted to build confidence in his plan to march to Italy. After crossing the Rhône, Hannibal began his journey toward the Alps. His soldiers traveled long distances each day, covering around 20 kilometers daily. Along the way, Hannibal made allies with local tribes who provided supplies for his journey.

Ascent of the Alps

We do not know for sure which path Hannibal and his army took through the Alps. Historians have debated this for many years. Some think it was the Little St Bernard Pass, while others suggest Col de Clapier, Col de la Traversette, or Col de Montgenèvre. Recent studies of soil and plants near Mont Cenis also give clues.

Hannibal faced challenges along his route. When his army reached a pass near Mt. Du Chat, local people tried to stop them. Hannibal used tricks and smart tactics to overcome these defenders. Later, near the Little St Bernard Pass, another group of locals tried to attack his army. Hannibal was ready for this and managed to protect his troops and supplies.

After resting, Hannibal led his tired and cold soldiers down from the mountains. He reminded them that they were close to their goal and showed them the land below, giving them hope to continue.

Descent to Italy

When Hannibal and his army reached the bottom of the Alps, they faced a very steep and dangerous path. The ground often melted during the day and froze again at night, making it hard to walk. Many soldiers slipped and fell, and sadly, some did not survive.

Along the way, the soldiers found a part of the path blocked by a landslide. Hannibal tried to find another route through deep snow, but it was too difficult. So, they went back and worked together to fix the path. After three days of hard work, they finally made it passable. The army then moved down to safer ground near modern Ivrea, marking the end of their tough journey across the Alps. They had started with many soldiers, but only a portion remained as they began their campaign in Italy during the Second Punic War.

In culture

In Jonathan Swift's Gulliver's Travels, the character Gulliver visits a magical island and talks to the spirit of Hannibal. They discuss the old story about Hannibal using fire and vinegar to melt rocks, and Gulliver learns it might just be a made-up story.

Artist Jacques-Louis David painted a famous picture in 1800 showing Napoleon crossing St. Bernard Pass. He even wrote Hannibal’s name on the rocks in the painting to compare Napoleon’s journey to Hannibal’s famous trip over the Alps.

In a 2005 episode of Doctor Who, called “World War Three,” a character mentions Hannibal’s crossing when talking about a clever way to defeat some aliens.

In a The Simpsons episode called "Cape Feare", some elephants walking over a character have words on their sides that refer to Hannibal’s famous journey.

In a 2016 comic book from IDW Publishing, called Godzilla: Rage Across Time, Godzilla creates problems for Hannibal as he moves toward Rome.

In 2025, a Swedish music group called Sabaton wrote a song named “Lightning at the Gates” about Hannibal’s big journey over the Alps. The song is part of their album called Legends.