Pope John VIII
In 2018, Michael E. Habicht, an archaeologist at Flinders University, published new evidence in support of an historical Pope Joan. Habicht and grapho-analyst Marguerite Spycher analyzed papal monograms on medieval coins and found that there were two significantly different monograms attributed to Pope John VIII. Habicht argues that the earlier monogram, which he dates from 856 to 858, belongs to Pope Joan, while the latter monogram, which he dates to after 875, belongs to Pope John VIII.