Ferdinand Magellan said he would finish the battle himself. After all, it was he who had ignored the warnings of his allied Philippine ruler, turned down the help of 1,000 neighboring natives and brought 60 of his crew members to face the islanders of Mactan with little preparation. After this retreat order, only a few of Magellan's crew members kept fighting by his side; the rest of them fled as the ever-boastful captain fell victim to the spears of Mactan's angry inhabitants.

This dramatic death fits Magellan's remarkable life—a life in which he traveled thousands of miles by boat and sailed seas previously unknown to Europeans. But something happened to Magellan on his trip around the world. His behavior shifted dramatically from the beginning to the end of the quest, according to a journal kept by Antonio Pigafetta, an Italian navigator whom Magellan hired to keep detailed documents of the voyage.

"When preparing, [Magellan] was apparently able to attract a lot of people to him and was very loyal to his Portuguese buddies," says historian Helen Nadar of the University of Arizona. "During the voyage, he became very different. He started treating his officers in a cruel way. He was very angry because some of the people mutinied."

Most of what is known about Magellan's life and voyage comes from Pigafetta's journal, along with some Portuguese government documents. More certain is the impact Ferdinand Magellan had on both the world of exploration and, through that, the world at large.

Born of noble blood in Portugal in 1480, Magellan worked in the Queen's household as a young boy, where he learned of the new discoveries happening around the world: Bartholomew Diaz rounding the Cape of Good Hope, Vasco da Gama journeying to India and Christopher Columbus discovering America. As he grew older, Magellan volunteered to sail under prestigious captains on long trips to foreign soil.

Around this time, the global spice trading industry was booming. Contrary to popular belief, Europeans highly regarded spices not because of their ability to mask bad meat, but to liven up their meals. "They did it for the taste," says Nadar. "Their meat was fresher then ours is because they slaughtered their meat daily." Jay Levenson, curator of "Encompassing the Globe," a new exhibit about Portugal at Smithsonian's Sackler Gallery and Museum of African Art, says spices also revealed social status. "They were so hard to get, they were a prestige item," he says. "A lot of people didn't even know where the Spice Islands were."

Portugal and Spain were not only competing for dominance in the spice industry, but also for influence in colonies around the world. King Manoel of Portugal was becoming increasingly frustrated with Spain's growing power in the East, especially in the Moluccas, commonly known as the Spice Islands, and was furious when Magellan pledged his allegiance to Spain and offered its king, Charles V, his plan to find an alternate route to India. This route would enable ships to pass from the Atlantic to the already discovered South Sea through South America.

Magellan had already sailed in the name of Portugal several times, but King Manoel had refused to compensate him when pirates looted his ship. Later, Magellan had fought in North Africa in the name of his homeland, but was still not paid.

Once Magellan persuaded King Charles to support his plan, Magellan took an oath of allegiance to Spain, breaking his promise to Portugal. "He couldn't go back to Portugal because he would be executed," says Nadar. "This was regarded as complete treason, perhaps more so because of the huge rivalry between Spain and Portugal at the time."

On August 10, 1519, Charles sent Magellan on his quest with five ships, and placed 265 men under his command. Most of these crewmembers were criminals, because many experienced sailors refused to support Magellan—perhaps because of his Portuguese background, argue some historians.

The journey proved difficult. The natives populating the southern tip of South America were very hostile to the Spaniards; previously, they had captured and eaten another, less-known Spanish explorer. When Magellan and his crew finally found a natural passage between the Atlantic and Pacific Oceans (now known as the Strait of Magellan), they thought it was only a large bay, much like the ones they had already encountered. To be sure it wasn't a strait, Magellan sent in two ships with strict orders to return within five days. During this time, however, a large storm passed over the fleet. As Magellan prepared to leave on the fifth day, the two ships returned and said the body of water was indeed a strait.

"Other Spanish voyages had tried to go through [the strait] and got lost," says Nadar. "Getting to the Pacific by ship, without having to go over land, was the biggest challenge of that period, and he's the one that solved it."

Thirty-three days and 344 miles later, Magellan and his crew reached what was then known as the New Sea, which Magellan named the Pacific for its peaceful waters. Like most Europeans at the time, however, Magellan thought Asia was much closer to South America than it actually is. The crew had expected to find many islands along the way to get food, water and other necessities, but did not. To make matters worse, Magellan steered the fleet too far north, possibly to avoid meeting any Portuguese ships, extending the voyage.

The crew lived without fresh food for more than three months. Hard rain and high wind complicated their travels, and the men were plagued with disease despite efforts to keep the boats sanitary. Over the course of the crossing, Magellan lost 19 crew members and one boat.

By the time the crew reached the Philippines, which they first thought to be the Spice Islands, Magellan had become intense and irrational. He didn't find any spices, instead deciding "to become the exclusive European merchant and official for one of the islands in the Philippines," says Nadar. Historical accounts show he joined one island ruler in trying to conquer another Philippine island. The most credible version of what happened next says Magellan insisted on only bringing 60 half-armed men into what is known today as "The Battle of Mactan" and refused any outside help, to show the natives his invincibility. The Spaniards were quickly defeated and Magellan was speared to death.

The remaining crew members continued back to Spain, though only 18 men and one boat returned safely. The strait, originally named Estrecho de Todos los Santos (Strait of All Saints) by Magellan, was renamed the Strait of Magellan by the Spanish king in the fallen explorer's honor.

Today, Magellan is still recognized as the first explorer to circumnavigate the globe, although he himself never completed the journey. His legacy lives on today in both Portuguese and Spanish cultures. "He was very much a part of the crucial generation of Portuguese that opened up eastern Asia," Levenson says. "He was an important figure in the history of Portuguese history, and then because of all the treatment he got, he became an important figure in Spanish history. It's quite interesting."