According to the later accounts, attested for the first time in the 17th century, in the papal election held after the death of Pope Adrian V he was elected to the papacy on September 5, 1276 and took the name Gregory XI, but having died the following day early in the morning, his election is not recorded as he was never proclaimed. Credibility of this story is contested by modern historians as unsupported by any contemporary source.
^This is according to Miranda, Salvator. 1998. "Consistory of June 3, 1273." However, in the bulls of Gregory X that contain subscriptions of the cardinals he is always preceded by Pedro Juliani, which puts into question the accuracy of this statement; cfr. the bulls published in Monumenta Boica, vol. 12, p. 138, and vol. 17 pp. 123-124.