Marco Polo (c. 1254 – January 8, 1324) was a merchant from the Venetian Republic who wrote Il Milione, which introduced Europeans to Central Asia and China. He learned about trading whilst his father and uncle, Niccolò and Maffeo, travelled through Asia and met Kublai Khan. In 1269, they returned to Venice to meet Marco for the first time. The three of them embarked on an epic journey to Asia, returning after 24 years to find Venice at war with Genoa; Marco was imprisoned, and dictated his stories to a cellmate. He was released in 1299, became a wealthy merchant, married and had 3 children. He died in 1324, and was buried in San Lorenzo.

Il Milione was translated, embellished, copied by hand and adapted; there is no authoritative version. It documents his father's journey to meet the Kublai Khan, who asked them to become ambassadors, and communicate with the pope. This led to Marco's quest, through Acre, into China and to the Mongol court. Marco wrote of his extensive travels throughout Asia on behalf of the Khan, and their eventual return after 15,000 miles (24,140 km) and 24 years of adventures. Their pioneering journey inspired Columbus and others. Marco Polo's other legacies include Venice Marco Polo Airport, the Marco Polo sheep, and several books and films. He also had an influence on European cartography, leading to the introduction of the Fra Mauro map.

The exact time and place of Marco Polo's birth are unknown, and current theories are mostly conjectural. However, the most quoted specific date is somewhere "around 1254", and it is generally accepted that Marco Polo was born in the Venetian Republic. While the exact birthplace is unknown, most biographers point towards Venice itself as Marco Polo's home town. His father Niccolò was a merchant who traded with the Middle East, becoming wealthy and achieving great prestige. Niccolò and his brother Maffeo set off on a trading voyage, before Marco was born. In 1260, Niccolò and Maffeo were residing in Constantinople when they foresaw a political change; they liquidated their assets into jewels and moved away. According to The Travels of Marco Polo, they passed through much of Asia, and met with the Kublai Khan. Meanwhile, Marco Polo's mother died, and he was raised by an aunt and uncle. Polo was well educated, and learned merchant subjects including foreign currency, appraising, and the handling of cargo ships, although he learned little or no Latin. In 1269, Niccolò and Maffeo returned to Venice, meeting Marco for the first time. In 1271, Marco Polo (at seventeen years of age), his father, and his uncle set off for Asia on the series of adventures that were later documented in Marco's book. They returned to Venice in 1295, 24 years later, with many riches and treasures. They had travelled almost 15,000 miles (24,140 km).

Upon their return, Venice was at war with Genoa, and Marco Polo was taken prisoner. He spent the few months of his imprisonment dictating a detailed account of his travels to fellow inmate, Rustichello da Pisa, who incorporated tales of his own as well as other collected anecdotes and current affairs from China. The book became known as The Travels of Marco Polo, and depicts the Polos' journeys throughout Asia, giving Europeans their first comprehensive look into the inner workings of the Far East, including China, India, and Japan. Marco Polo was finally released from captivity in August 1299, and returned home to Venice, where his father and uncle had purchased a large house in the central quarter named contrada San Giovanni Crisostomo. The company continued its activities and Marco soon became a wealthy merchant. Polo financed other expeditions, but never left Venice again. In 1300, he married Donata Badoer, the daughter of Vitale Badoer, a merchant. They had three daughters, called Fantina, Bellela and Moreta.

In 1323, Polo was confined to bed, due to illness. On January 8, 1324, despite physicians' efforts to treat him, Polo was on his deathbed. To write and certify the will, his family requested Giovanni Giustiniani, a priest of San Procolo. His wife, Donata, and his three daughters were appointed by him as co-executrices. The church was entitled by law to a portion of his estate; he approved of this and ordered that a further sum be paid to the convent of San Lorenzo, the place where he wished to be buried. He also set free a "Tartar slave" who may have accompanied him from Asia. He divided up the rest of his assets, including several properties, between individuals, religious institutions, and every guild and fraternity to which he belonged. He also wrote-off multiple debts including 300 lire that his sister-in-law owed him, and others for the convent of San Giovanni, San Paolo of the Order of Preachers, and a cleric named Friar Benvenuto. He ordered 220 soldi be paid to Giovanni Giustiniani for his work as a notary and his prayers. The will, which was not signed by Polo, but was validated by then relevant "signum manus" rule, by which the testator only had to touch the document to make it abide to the rule of law, was dated January 9, 1324. Due to the Venetian law stating that the day ends at sunset, the exact date of Marco Polo's death cannot be determined, but it was between the sunsets of January 8 and 9, 1324.

An authoritative version of Marco Polo's book does not exist, and the early manuscripts differ significantly. The published versions of his book either rely on single scripts, blend multiple versions together or add notes to clarify, for example in the English translation by Henry Yule. Another English translation by A.C. Moule and Paul Pelliot, published in 1938, is based on the Latin manuscript which was found in the library of the Cathedral of Toledo in 1932, and is 50% longer than other versions. Approximately 150 variants in various languages are known to exist, and without the availability of a printing press many errors were made during copying and translation, resulting in many discrepancies.

The book starts with a preface about his father and uncle traveling to Bolghar where Prince Berke Khan lived. A year later, they went to Ukek and continued to Bukhara. There, an envoy from Levant invited them to meet Kublai Khan, who had never met Europeans. In 1266, they reached the seat of the Kublai Khan at Dadu, present day Beijing, China. Khan received the brothers with hospitality and asked them many questions regarding the European legal and political system. He also inquired about the Pope and Church in Rome. After the brothers answered the questions he tasked them with delivering a letter to the Pope, requesting 100 Christians acquainted with the Seven Arts (grammar, rhetoric, logic, geometry, arithmetic, music and astronomy). Kublai Khan requested that an envoy bring him back oil of the lamp in Jerusalem. The long sede vacante between the death of Pope Clement IV in 1268 and the election of his successor delayed the Polos in fulfilling Khan's request. They followed the suggestion of Theobald Visconti, then papal legate for the realm of Egypt, and returned to Venice in 1269 or 1270 to await the nomination of the new Pope, which allowed Marco to see his father for the first time, at the age of fifteen or sixteen.

In 1271, Niccolò, Maffeo and Marco Polo embarked on their voyage to fulfill Khan's request. They sailed to Acre, and then rode on camels to the Persian port of Hormuz. They wanted to sail to China, but the ships there were not seaworthy, so they continued overland until reaching Khan's summer palace in Shangdu, near present-day Zhangjiakou. Three and one-half years after leaving Venice, when Marco was about 21 years old, Khan welcomed the Polos into his palace. The exact date of their arrival is unknown, but scholars estimate it to be between 1271 and 1275. On reaching the Mongol court, the Polos presented the sacred oil from Jerusalem and the papal letters to their patron. Marco knew four languages, and the family had accumulated a great deal of knowledge and experience that was useful to Khan. It is possible that he became a government official; he wrote about many imperial visits to China's southern and eastern provinces, the far south and Burma.

Kublai Khan declined the Polos' requests to leave China. They became worried about returning home safely, believing that if Khan died, his enemies might turn against them because of their close involvement with the ruler. In 1292, Khan's great-nephew, then ruler of Persia, sent representatives to China in search of a potential wife, and they asked the Polos to accompany them, so they were permitted to return to Persia with the wedding party — which left that same year from Zaitun in southern China on a fleet of 14 junks. The party sailed to the port of Singapore, travelled north to Sumatra and around the southern tip of India, eventually crossing the Arabian Sea to Hormuz. The two-years voyage was a perilous one - of the six hundred people (not including the crew) in the convoy only eighteen had survived (including all three Polos). The Polos left the wedding party after reaching Hormuz and travelled overland to the port of Trebizond on the Black Sea, the present day Trabzon.