I’ve been reading Bob Curran’s book Unholy Popes, an extremely amusing chronicle of papal misbehavior over the centuries and the more infamous scandals and shenanigans attributed to the various men who’ve held the seat. There have been periods of decades when Rome was rife with corruption, nepotism, bribery, and at times, open warfare and murder over the papal succession. There have been times when no one was pope and times when there were multiple contenders, each one claiming to be the true pope and threatening the others with excommunication. There have been popes who were so depraved that the Catholic Church itself has retroactively denounced them, declared them antipopes or attempted to erase them from the history books.

It’s one of these stories that lies at the root of a bizarre but true fact: The current pope is misnumbered. By the church’s own reckoning, Benedict XVI has the wrong number – and by so titling himself, he’s tacitly acknowledged the reign of a heretic!

The explanation of this dates back to the 11th century. At that time, the German emperor Henry III had the power of choosing the pope and had installed a series of German bishops in the office. In 1057, his previous pick, Pope Victor II, died. Under the terms of a treaty, Rome was obliged to consult with Henry to nominate a successor, but they failed to do this. Several powerful Roman families instead chose their own candidate for the papacy, Stephen IX, who reigned less than a year before dying of illness. Before his death, he expressed a wish that one of his advisers, Hildebrand, should select the next pope.

But the Roman noble families ignored this wish. They chose another candidate: John Mincius, the cardinal-bishop of Valletri, who took the title Benedict X. A number of cardinals claimed the election was unjust and had been determined by bribery; they were forced to flee Rome by Benedict X and his supporters.

When word reached Hildebrand, who was at the German imperial court, he decided to take action. Together with the cardinals who’d fled Rome, they met and chose Gerhard of Burgundy, bishop of Florence, as the next pope. Taking the name Nicholas II, the new pope pronounced Benedict X an antipope, declared him to be excommunicated, and proceeded to Rome backed by an army organized by sympathetic noblemen. After several inconclusive battles with Benedict’s supporters, Nicholas was victorious in a 1059 clash at Campagna, and Benedict surrendered and renounced the papacy. Nicholas allowed him to go free, but when Hildebrand returned from Germany in 1060, he had Benedict arrested and imprisoned until his death sometime between 1070 and 1080.

Hildebrand himself became pope in 1073, taking the name Pope Gregory VII. During his reign, he declared that Benedict X was not only excommunicated but had never been pope, and that any acknowledgment of him as such would be treated as heresy and punished with automatic excommunication. But the next pope who took the name Benedict, in 1303, declared himself to be Benedict XI – implicitly acknowledging his predecessor, despite the pleas of the Curia – and all subsequent Benedicts, including the current one, have followed suit.

If you look at official records, it’s obvious that the church is embarrassed by the whole affair. The New Advent Catholic encyclopedia’s entry for Benedict X says in its entirety, “The bearer of this name was an antipope in the days of Nicholas II, 1056-61.” But this terse note can’t disguise the problem: If Benedict X was an antipope, why is it that the next pope who took the name was Benedict XI? Shouldn’t he have been Benedict X, since the “first” Benedict X was an illegitimate pretender to the throne? And doesn’t this mean that every Benedict since, including the one that’s now pope, have perpetuated this error and acknowledged the legitimacy of a man earlier denounced as a usurper, an antipope and a heretic?