Commines was born at Renescure, Flanders, to an outwardly wealthy family. However, his father's death in 1453 left him the orphaned owner of an estate saddled with enormous debts. In his teens he was taken into the care of Philip the Good (1419-1467), Duke of Burgundy, who was his godfather. He fought at the Battle of Montlhery in 1465 and the Battle of Brusthem in 1467 but in general seems to have kept a low profile.
In 1468, he became a knight in the household of Charles the Bold, Philip's son who succeeded to the dukedom in 1467, and thereafter he moved in the most exalted circles, being party to many important decisions and present at history-making events. A key event in Commines's life seems to have been the meeting between Charles and Louis XI of France at Péronne in October 1468. Although Commines's own account skates over the details, it is apparent from other contemporary sources that Louis believed Commines had saved his life. This may explain Louis's later enthusiasm in wooing him away from the Burgundians.
In 1470 Commines was sent on an embassy to Calais, then an English possession. It is unlikely that he ever visited England itself, what he knew of its politics and personalities coming mostly from meetings with exiles, both Yorkist and Lancastrian; these included Henry Tudor and Warwick the Kingmaker. He also met King Edward IV of England during the latter's continental exile and later wrote a description of his appearance and character.
Commines was a great favorite with Duke Charles for seven years (going back to when he had still been Count of Charolais). The 19th-century "man of letters", Isaac D'Israeli, recounts that one day, when they came home from hunting and were joking around as was their wont within the "family", Commines "ordered" the prince to remove Commines's boots as if he was a servant; laughing, the prince did so but then tossed the boot at Commines, and it bloodied his nose. Everyone in the Burgundian court started calling Commines "booted head".
D'Israeli says Commines so resented that nickname that it was the reason he suddenly left Burgundy and went into the service of the French king, but the financial incentives offered by Louis provide a more than adequate explanation for Commines to turn his coat: He was still heavily burdened with his father's debts. Commines fled by night from Normandy on August 7, 1472, and joined Louis near Angers. On the following morning, when Duke Charles discovered his servant and god-brother missing, he confiscated all Commines's property. Louis was generous in making up for those losses.
As a long-time enemy of Burgundy, Louis no doubt valued the inside information Commines was able to provide, and Commines quickly became one of the king's most trusted advisers. Jean Dufournet's 1966 study of Commines has shown that the next five years, up to 1477, were the most prosperous from Commines's point of view, and the only ones when he truly had Louis's confidence. Dufournet's observations come as no surprise to anyone familiar with the modern political diarist. After Charles's death in 1477, the two men openly disagreed about how best to take political advantage of the situation. Commines himself admitted associating with some of the king's most prominent opponents and referred to another incident, in May 1478, when Louis reprimanded him for allegedly being open to bribery. Thereafter, much of his diplomatic work was done in the Italian arena, and he came into contact with Lorenzo de Medici on several occasions.
When Louis began to suffer ill-health, Commines was apparently welcomed back into the fold and performed personal services for the king. Many of his activities during the period seem to have involved a degree of secrecy; he was effectively acting as a kind of undercover agent. However, he never regained the level of intimacy with the king that he had previously enjoyed, and Louis's death in 1483, when Commines was still only in his thirties, left him without many friends at court. Nevertheless, he retained a place on the royal council until 1485. Then, having been implicated in the Orleanist rebellion, he was taken prisoner and kept in confinement for over two years, from January 1487 until March 1489. For some of that period, he was kept in an iron cage.
After his release, Commines was exiled to his estate at Dreux, where he began to write his Mémoires. (This title was not used until an edition of 1552.) By 1490, however, he was recovering his position at court and was in the service of King Charles VIII of France. Charles never allowed him the privileged position he had held under Louis, and he was once again used as an envoy to the Italian states. However, his personal affairs were still problematic, and his right to some of the possessions given him by Louis was subject to legal challenges.
In 1498 (fifteen years after the death of Richard III of England), Commines's work was published, and it has been regarded as a historical record of immense importance, largely because of its author's cynical and forthright attitude to the events and machinations he had witnessed. His writings reveal many of the less savory aspects of the reign of Louis XI, and Commines related them without apology, insisting that the late king's virtues outweighed his vices. He is regarded as a major primary source for 15th century European history.
Isaac D'Israeli said in his 1824 Curiosities of Literature that Commines's hatred for the duke of Burgundy poisoned everything he wrote about him, but D'Israeli also pointed out that other historians had virtually never been "honest" about what they wrote, either:
Commines' scepticism is summed up in his own words: Car ceux qui gagnent en ont toujours l'honneur ("For the honours always go to the winners"). Some have disputed whether his candid phrases disguise a deeper dishonesty. Yet at no time does he attempt to present himself as a hero, even when recounting his military career. His attitude to politics is one of pragmatism, and his ideas are practical and progressive. His reflections on the events he has witnessed are profound by comparison with those of Froissart, who lived a century earlier. His psychological insights into the behaviour of kings are ahead of their time, reminiscent in some ways of his contemporary, Machiavelli. Like Machiavelli, Commines aims to instruct the reader in statecraft, though from a slightly different viewpoint. In particular, he notes how Louis repeatedly got the better of the English, not by military might, but by political machination.