Incredibly, a mere 120 years after Muhammad's followers triumphed over unbelievers within his own tribe at the Battle of Badr, the armies of Arabia were far to the east, clashing with the forces of Imperial Tang China.
The two met at the Talas River, in modern-day Kyrgyzstan, and the larger Tang Army was decimated.
Faced with long supply lines, the Abbassid Arabs did not pursue their defeated foe into China proper.
Nonetheless, this resounding defeat undermined Chinese influence across Central Asia, and resulted in the gradual conversion of most Central Asians to Islam.
It also resulted in the introduction of new technology to the western world, the art of papermaking.