Page 302

302 A HISTORY OF THE CRUSADES 50.See above, pp. 211—212.51.See above,
pp. 147—148, where the summer of 1376 is considered more likely. 
 On August 10, 1376, the master, Robert of Juilly, wrote of a passagium ad
partes ducatus Athenarum, presumably intended to defend the Catalans of Thebes
and Athens against the Turks; the Catalans, in fact, were so weak that in
1374 they were unable to prevent Nerio Acciajuoli of Corinth from seizing
Megara.50 These plans had to be changed when hopes of ecclesiastical union
and military cooperation with the Greeks were ruined by a new war between
Genoa and Venice, and by the intervention of both parties, and also of the
Turks, in increasing civil strife within Byzantium. The passagium was further
delayed while Gregory XI left Avignon late in 1376 and sailed slowly to Rome,
with a fleet commanded by Fer nández de Heredia. The pope continued
to encourage elaborate preparations for the expedition, the destination of
which was changed during the summer from the Aegean to the Adriatic. In about
June 1377 the principality of Achaea was leased by the Hospital for five
years from queen Joanna I of Naples, and a Hospitaller, Daniel del Carretto,
was sent as bailie and took over the government of the Latin Morea.51 Negotiations
with Maddalena de' Buondelmonti (the widow of Leonard I Tocco, duke of Leucadia
and count of Cephalonia), who was acting as regent for her two sons, were
completed in October; from Maddalena the Hospitallers acquired Vonitsa, a
port on the Gulf of Arta in Epirus which for some years had been subject
to attacks from the Albanian forces of Ghin Boua Spata, lord of Arta, and
which provided a gateway into northern Greece. Robert of Juilly died on July
27, 1377, and on October 24 Gregory XI, having previously reserved the provision
pro hac vice, appointed Fernández de Heredia in his place. In response
to vigorous protests from the Convent, Gregory had to promise that the Hospi
tal's privileges would not again be flouted by such a provision. 
 The new master left Naples with the passagium around the begin ning of 1378,
accompanied by Francis and Esau de' Buondelmonti, Maddalena's brothers, and
by various other Florentines who helped with financial, transport, and supply
problems, apparently in the hope of commercial advantage. By April a rather
small force of Hospitallers, which included the admiral, Palamedo Giovanni,
and the priors of Venice, Pisa, and Capua, was at Vonitsa. There they delayed,
apparently because the new pope Urban VI, elected on April 8, failed to send
the necessary reinforcements. By summer, when the expedition advanced inland
and attacked the walls of Arta with siege engines, Ghin Boua Spata had been
given time to collect