There have been eight Popes and Antipopes named Alexander.
Pope Alexander I (c. 106 – c. 115)
Pope Alexander II (1061–1073)
Pope Alexander III (1159–1181)
Pope Alexander IV (1254–1261)
Antipope Alexander V (1409–1410) (Considered to be an Antipope; however, the next Pope Alexander took the name Alexander VI due to confusion over Alexander V’s status at the time.)
Pope Alexander VI (1492–1503)
Pope Alexander VII (1655–1667)
Pope Alexander VIII (1689–1691)
Excuse me ~ the successor to Pope Alexander V ~ Antipope John XXIII ~ was a priest for one day but had earlier held office as Cardinal although he was a layman. At the time of his election numerous countries recognized him as pope. Currently the Catholic church does not consider him a pope ~ just one of a number of antipopes back in the middle ages during a schism. Alexander VI was Borja ~ and his father’s surname in one of its manifestations clearly links him to the Bishop of St. Malo ~ who actually provided Alexander VI some assistance during a period of duress. BTW, I had glossed over the Bishop of St. Malo in previous reads of the Catholic Encyclopedia ~ now I have to go back and start matching up some more Spanish nobles with Breton noble families. I’d imagine at the time this stuff was fairly well known or understood. Britany was a great power in the 1400s. They had most of the gold known to exist in Europe and played neutral to England and France in the 100 years war ~ while simultaneously keeping Spain well provided with knights for the Reconquista.