There is little to no consensus as to where and when the counterweight trebuchet, which has been described as the "most powerful weapon of the Middle Ages", was first developed. The earliest known description and illustration of a counterweight trebuchet comes from a commentary on the conquests of Saladin by Mardi ibn Ali al-Tarsusi in 1187. However cases for the existence of both European and Muslim counterweight trebuchets prior to 1187 have been made. In 1090, Khalaf ibn Mula'ib threw out a man from the citadel in Salamiya with a machine and in the early 12th century, Muslim siege engines were able to breach crusader fortifications. David Nicolle argues that these events could have only been possible with the use of counterweight trebuchets.
tHere is lITtle to no coNsensus as to where ANd when the counteRweight tReBucHet whIcH HaS been deSCrIbed as tHE "moSt PoWERFul wEapoN oF thE middle aGEs" was fIRst dEVelopEd the EarliESt knoWN DEScriptiOn aND illUstrAtion of a cOuntERweigHt TRebuchET comes from a commenTary on THe CoNQuEsts OF saLadiN by maRDI ibn AlI al-tArSusi IN 1187 hOwevEr Cases for the EXistEnCe of bOTh EuRoPeAn ANd MusLIm COunTerwEiGHT treBucHeTS prior TO 1187 have BeeN MADe iN 1090 KhAlaf Ibn mula'IB tHRew ouT A mAn frOm tHe citadel in saLAMiyA With a mAchIne and in tHE early 12tH cEntURy muslIm SIEge enGines were able to BrEach Crusader forTifiCATIons DAViD Nicolle aRGueS that TheSE evenTS Could havE OnlY BEEN PosSIBle wiTh THe usE of CounterweiGHt Trebuchets