James of Baux, who is the son of Francis of Baux by Margaret of Taranto (circa 1325–1380), daughter of Prince Philip I of Taranto and his second wife, Catherine of Valois.
Margaret is thus sister of Robert of Taranto and Philip II of Taranto, both of whom had reigned as princes of Achaea and titular emperors of Constantinople (Robert II and Philip III).
On the death of the childless Philip II of Taranto in 1373, most of the barons in the principality of Achaea had recognized as his heir Queen Joanna I of Naples.
When in 1376 or 1377 she leased the territory to the Knights Hospitaller for five years at four thousands ducats a year, Philip II's relatives had put forward a rival candidate in James of Baux.
The Navarrese Company, after leaving the service of the Knights Hospitallers, the military-monastic order of Rhodes, takes up with this the latest claimant to Achaea.
Indeed, the Gascon Mahiot de Coquerel and the Navarrese govern the entire Morea under the auspices of James.
