Still, few readers of Laurence Bergreen’s new biography, “Casanova: The World of a Seductive Genius,” will emerge from it wholly disapproving of this remarkable man. Casanova’s charm was evidently prodigious; he could win over old popes as well as young girls. His saving graces included limitless curiosity, resilience and joie de vivre, as he bounced shamelessly from one misadventure to the next. He cheerfully acknowledged at the end of his life that he was the main cause of all his misfortunes.

Bergreen has often written about explorers; his other books include studies of Christopher Columbus, Ferdinand Magellan, Marco Polo and NASA’s mission to Mars. Perhaps Casanova should be counted as an explorer, too, or at least as a travel writer, even though his journeys were confined to Europe. Much of his life was spent rattling across the continent in coaches. Rather often, he was on the run — he was forced to flee his native Venice at least three times — but mostly he was letting himself go “wherever the wind . . . drove me.” In his teens, he shuttled between Venice, Rome, Constantinople and Corfu; in his 20s it was Parma, Geneva, Lyon, Paris, Dresden, Prague and Vienna; in his 30s, Amsterdam, Geneva, Zurich, Stuttgart, Naples, Rome, Florence, Modena, Munich, Paris, Turin, London and beyond. And so it went until his late 50s, when his luck and money ran out, and he took a job as librarian in a dismal castle in Bohemia and wrote up his adventures.

The resulting tome may be the longest autobiography ever published, running to over 3,500 handwritten pages. When unadulterated versions emerged, in the 1960s, it was recognized as a uniquely panoramic and unvarnished portrait of 18th-century Europe. Casanova moved with ease in all strata of society. As well as hordes of nobility, he met Benjamin Franklin, Bonnie Prince Charlie, Frederick the Great, Catherine the Great, Pope Clement XIII, Rousseau, Voltaire and Mozart. He mixed with financiers, ambassadors, Freemasons, magicians and government ministers, in addition to an awful lot of gamblers, rakes, actors, dancers, courtesans and common prostitutes.

Perhaps his most famous exploit was his escape, after 15 months of miserable incarceration, from one of Venice’s state prisons, known as I Piombi, to which he was confined in 1755 at the age of 30, ostensibly for irreligion. This was the story he was most often asked to tell, and the account of it he published in 1788 was one of the few literary successes of his lifetime. He also wrote poems, a translation of Homer into ottava rima, librettos, some pamphlets on mathematics, historical studies on Poland and Venice and — among other things — a five-volume work of science fiction set in the Earth’s interior. He envied the literary fame of Goethe and Voltaire, and could not quite understand why they were more highly regarded than he was.

The desire for renown as a man of letters came early for Casanova, as most things did. By his account, it arrived around the age of 11, when he stunned the diners at his tutor’s house with a risqué Latin witticism. At about the same time, the tutor’s younger sister gave him his first taste of sex. The other achievements of his adolescence included a doctorate of law awarded at the age of 16, expulsion from a monastery, a spell as a trainee priest, a love affair with a putative castrato (whom Casanova correctly believed to be a girl in disguise), a stint in the army, various other affairs and the start of his mostly unsuccessful gambling career.