The Orlando Innamorato in English translation, Book I, Canto X, Stanzas 21-40 Notes
30. Cousin german. First cousins. I strongly suspect Uldano is Boiardo’s invention, or at most a very minor character in the romances of Ogier.
38. Stained with heresy. The Armenians, the first nation to adopt Christianity (several decades before the Roman Empire), succumbed to the Monophysite heresy in the 500’s. Subsequent attempts at reunion have met with only very limited success.
Emperor of Trebisond. After the fall of Constantinople to the Fourth Crusade in 1204, several rump states arose, all claiming the Imperial legacy. The longest lived of these was Trebisond on the Black Sea, which refused to submit to the Greek Emperors when they reclaimed their city in 1261. Trebisond actually outlasted Constantinople, and did not fall to the Turks until 1461.
39. Roase. Mesopotamia.