The most valuable source for the history of the early crusades the Kingdom of Jerusalem is undoubtedly William of Tyre's A History of Deeds Done Beyond The Sea. A work of great scholarship careful detail, it is particularly important in that William was Chancellor of the Kingdom of Jerusalem from 1174 Archbishop of Tyre from 1175 to his death c. 1185 so was closely placed to the political decision making of the period. William was also a careful highly educated scholar; although born in Jerusalem, he spent twenty years among the leading intellectuals of France Italy and, after pursuing an avid interest in the liberal arts, devoted himself to civil law the teachings of the masters at Bologna.1 In this respect William is far more than a narrator of crusading history, for which he would be highly regarded; he is also an important figure in the intellectual advances of the twelfth century. A close examination of William's vocabulary of social order shows that in his work he advanced the evolution of twelfth-century social concepts also shed some light on the social structure of the Kingdom of Jerusalem.The History was commissioned by King Amalric of Jerusalem in 1167 took its final form after redrafting by William in 1184, it is clear that in his work William reveals a very rich vocabulary to describe social classes (see appendix). William actually uses the term classis to mean a social category of person. Current scholarship in history, sociology, political theory would consider it anachronistic to talk about class in the twelfth century. Indeed, the use of classis as a term for social category must have been extremely rare as even such eminent scholars of lexicographers as Charles Dufresne Du Cange Jan Frederik Niermeyer do not note it.Insofar as medieval writers before William discussed society, they referred to ordines, the orders of society. In the early part of the eleventh century even the most advanced discussion of the subject of class had not progressed beyond the work of Adalbero, Bishop of Laon, Gerard, Bishop of Cambrai, writing c. 1025, who had articulated the famous tripartite division of society according to function-those who pray, those who fight, those who labor.2William uses the term ordo to mean order in the theological sense ordines to indicate social order, but equally often he uses the term classis for the same purpose. For example, in describing the character of Baldwin III, he writes that [Baldwin] acquired so great favor to himself from the commoners the greater people that he was more popular with both classes [classis] than his predecessors.3 After the defeat of King Louis VII at Mount Cadmus, 7 January 1148, during the second Crusade, William describes how the women fearfully cast about during for the return of fathers, lords, husbands, sons: and while they did not find what they sought they spent the night kept awake by the burden of their cares ... nevertheless returned in the night some of each of these classes [classis].4Classis also appears in the phrase secundae classis homines, a phrase used three times to indicate a category of middle-class person. In describing the distant origins of the Hospitallers he says that it was a time when there also flocked [to Jerusalem] some of the other nations, both nobles the second class of men.5 At the fall of Balbis (3 November 1168) King Amalric's troops, scarcely spared the old people children, were not any more merciful to the second class of persons.6 For his campaign beginning December 1170 the king's formidable opponent Saladin increased his army with commoners the second class of people.7 It is interesting to note that in these last two examples the term is referring to Muslim society, which William must have considered as socially diverse as his own. The existence activity of a middle class of person as subjects of his history required William to use similar phrases throughout his work such as mediae manus hominum, secundae manus homines, inferioris manus homines. …