Latin Treuga Dei, or Treva Dei. In the 10c Wido, bishop of Puy, persuaded knights and peasants to swear to protect Church property and not to plunder. At a more formal level, it can be traced back to the *Synod of Elne in 1027, which suspended all warfare from Saturday night until prime on Monday. This oath-taking spread widely, with the pacific intent deepening until, in theory, there were left only 80 days in any year in which waging war was permissible. To begin with, war was not permitted between sunset on Wednesday and sunrise on Monday of each week; saints' days also were included, as were festivals. The truce lasted during the seasons of Lent and Advent, the three great vigils and feasts of the Blessed Virgin, and those of the 12 apostles and a few other saints. The Synod of Therouanne decreed a Truce of God in 1063, while the Council of Clermont in 1095 pronounced a truce for all Christendom. Such a truce was impractical, but it grew from a noble impulse. It was precursor to the king's peace in England, where the kind of private warring which occurred on the continent, at which the truce was aimed, was not possible. The avowed purpose of the 'truce' was to prevent Christian from fighting and killing Christian, esp. when there were so many infidels in the world and the Holy Land needed liberation. -
Cf. Fighting season
Dictionary of Medieval Terms and Phrases. Christopher Coredon with Ann Williams.