Excerpt from "Frederick II to Henry III of England," in Roger of Wendover's Flores Historiarum (1229)
Originally written by Frederick II; Reprinted in Liber qui dictiur Flores Historiarum ab anno Domini MCLIV annoque Henrici Anglorum regis Secundi primo; Edited by H. G. Hewlett; Published in 1886–89

Excerpt from Matthew Paris's Chronica Majora (1258)
Originally written by Gerold, Patriarch of Jerusalem; Reprinted in "Letters of the Crusaders," in Translations and Reprints from the Original Sources of European History; Translated by Dana C. Munro; Published in 1896

The disasters of the Fourth Crusade in 1204 and of the so-called Children's Crusade in 1212 left the Christian world worried about the fate of the Holy Land. Pope Innocent III continued to call...