Pope John XVIII - Confusion Over Ordinals

Confusion Over Ordinals

Pope John XVIII was only the seventeenth pope called John, because John XVI (997–998) was an antipope according to official reckoning. His status as an antipope was not recognized at the time, however, so the true sixteenth Pope John called himself John XVII. The true seventeenth pope called John took the regnal number XVIII. The true sequence of numbering has never been corrected.