George Gemistos Plethon:
chrono by al klisiak

c. 1335-1360 b. 
c. 1370- Accompanies Emperor John Palaeogus to Western
Europe.
afterward returns to Greece, settles in Misithra where
he spends the majority of his life
1433 Theodore II grants Gemistos territorial
privileges
1438 Returns with the Emperor to Italy, designated one
of the six champions of the Orthodox Church in the
council of Florence
1439 "On the differences between Aristotle from Plato"
(De Differentiis) written
1440 "Laws" written
1441 Returns to Peloponnesus
c.1448-49 Gemistos writes his "Reply"
1450 d. and buried at Misithra
1465 Remains carried to Rimini and placed at the
Chrurch of St. Francis--with an inscription:
"Thimistius Byzantius"
1541 "Laws" printed
1574 " De Differntiis " Publ. at Basle.

from, "George Gemistos Plethon; the Last of the
Hellenes"  by C.M. Woodhouse. And the Catholic
Encyclopedia