All to the sword

#OTD in 1121 King David IV of Georgia defeated the Seljuk Turks at the battle of Didgori, still celebrated in modern Georgia. 

David was up against a large Islamic coalition led by Najm al-Din Ilghazi, who had formerly ruled the Armenian principality of Mayafariquin on the upper Tigris. The sources are conflicting, but it is clear that David's army was heavily outnumbered. He did, however, have a large number of heavy cavalry. These included his personal retinue, the 'mona-spa', and several hundred Frankish knights. 

On the day of battle, the Georgians lured the much larger Seljuk host into a mountainous and wooded area near the Didgori mountain range, west of Tbilisi. At David's signal, his men sprung the trap and charged down from the mountain sides, catching the Seljuks in a pincer movement. After heavy fighting, many of the Seljuk leaders were killed or captured, triggering the collapse of their demoralised army. 

Thousands were slaughtered in the rout. A Georgian chronicler said that David's men pursued the Seljuks for three days, "putting all of them to the sword and leaving them to the carnivorous beasts and birds of the mountains and plains” of the Manglisi Valley. A Frankish chronicler, Matthew of Edessa, wrote that:  

"...terrible and savage slaughter of the enemy troops ensued and the [enemy] corpses filled up the rivers and covered all valleys and cliffs." 

Allowing for exaggeration, this was clearly a disastrous defeat for the Seljuks. A triumph for the Georgians, it was also splendid news for the Roman Emperor, John II, who was allied to David. Between them, the allies were rolling back the Seljuks on two fronts at once.