How did Sultan Mehmed II overcome the impenetrable walls of Constantinople? What could Constantine XI have done to avoid being the last Roman emperor? And were the youthful Ottoman forces hopped up on religious exuberance, or just sugar?   Links To Further Yer Book-Learnin’   Sultan Mehmed II or Mehmed the Conqueror (1432–1481), was a merciless warrior who slaughtered millions, conquered vast territories, and just loved to doodle.   Constantine I (The Great) (272-337) was the first emperor of Byzantium, and Constantine XI Dragases Palaiologos or Dragaš Palaeologus (1404–1453) was the last. Many Greeks saw it as fitting that the Byzantine Empire, or Eastern Roman Empire, started with one Constantine and ended with another. Constantine XI was less keen on being the Byzantine bookend.   Istanbul got its name in 1930. Not, ahem, in 1935, as said in the episode. You’d think Trent would have noticed this on his visit in 1933. The shame.   In 1953 — the 500-year anniversary of Constantinople’s conquest — Canadian heartthrobs The Four Lads sung the novelty hit Istanbul (Not Constantinople). The song became a gold record, and endures as an ear worm for history geeks.