He initiated and established the two great trade caravan journeys of Quraish from Mecca, the Caravan of Winter to Yemen and the Caravan of Summer to north-west Arabia, and beyond it to Palestine and Syria, which were then under Byzantine rule as part of the Roman Empire. After obtaining privileges from the Ghassanid king of Syria, even went in person to Byzantium and procured an edict from the Byzantine Roman Caesar, exempting Quraish from duties or taxes when operating in the countries under his domain. Caesar also wrote to the King Negus of Abyssinia to admit the Quraish there for trade, and Hashim's brother 'Abd Shams had a special permit with him. Muttalib had his treaty with the Himyarites of Yemen, and their half-brother Nawfal with the Persian governments of Iraq and Iran.