Assizes of Jerusalem

The Assizes of Jerusalem are a collection of numerous medieval legal treatises containing the law of the crusader Kingdom of Jerusalem and Kingdom of Cyprus. They were compiled in the thirteenth century, and are the largest collection of surviving medieval laws.

As Peter Edbury says: "one group of sources from the Latin East that have long excited the attention of scholars are the legal treatises often known collectively, if somewhat misleadingly, as the Assises of Jerusalem." (Peter W. Edbury, John of Ibelin and the Kingdom of Jerusalem, pref.)

The assizes, or assises in French, survive in written form only from the 13th century, at least a generation after the collapse of the Kingdom of Jerusalem. The earliest laws of the Kingdom were promulgated at the Council of Nablus in 1120, but these laws seem to have fallen out of use and were replaced by the assizes by the 13th century and presumably even earlier.

Although no laws or court cases survive from the height of the kingdom in the 12th century, the kingdom obviously had laws and a well-developed legal structure. By the 13th century, the development of this structure was lost to memory, but jurists such as Philip and John recounted the legends that had grown up about the early kingdom. According to them, both the Haute Cour and the burgess court were established in 1099 by Godfrey of Bouillon, who set himself up as judge of the high court. The laws of both were said to have been written down from the very beginning in 1099, and were simply lost when Jerusalem was captured by Saladin in 1187. These laws were kept in a chest in the Church of the Holy Sepulchre, and were thus known in Old French as the "Letres dou Sepulcre." The chest supposedly could have only been opened by the king, the Patriarch of Jerusalem, and the viscount of Jerusalem. Each law, according to Philip, was written on one page, beginning with a large initial illuminated in gold, and with a rubric written in red ink. Philip claimed to have obtained his information from an old knight and jurist named Ralph of Tiberias, and John in turn probably got his information from Philip. Whether or not these legends were true (Edbury, for one, believes they were not), the 13th century jurists envisioned the legal structure of the kingdom to have existed continuously from the original conquest.

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