Lethold of Doornik or Letholdus was the first Flemish Christian knight over the walls of Jerusalem during the siege of Jerusalem of 1099, essentially ending the First Crusade, according to a contemporary account by an unknown eyewitness. It is said that when the Muslims saw Lethold emerge over the walls, many of them began to retreat further into Jerusalem.Asbridge, Thomas (2004). "The First Crusade, A New History," Oxford University Press. p. 315.
See also Tancred, Prince of Galilee - alternative claimant of "the first Christian knight over the walls of Jerusalem "
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