al-Harith ibn Umayr al-Azdi RA

Al-Harith ibn Umayr al-Azdi RA was the Prophet ﷺ's envoy carrying a letter to Heraclius. Passing through Ghassanid lands, he was captured, tortured and killed by their chieftain Shurahbil ibn Amr with his own hand, a grave violation of the universal custom protecting envoys. According to al-Waqidi, his killing was the reason the Prophet ﷺ sent the army to Mu'tah in 8 AH.