The Battle of Yarmuk

Khalid ibn al-Walid ﵁ led the Muslim force northward out of southern Syria, from the corridor between Maʿan and Bosra, in three to four separate columns. Above them rose the Yarmuk plateau, a vast table of twelve to fifteen kilometers north-south and eight to ten kilometers east-west, enclosed by three deep wadi gorges of nearly two hundred meters. Wadi al-Yarmuk in the south, Wadi al-Ruqqad in the west with the crucial passage at Ayn Dhakar, and Wadi al-Allah in the east.

Abu ʿUbayda ibn al-Jarrah ﵁ was the nominal supreme commander, appointed by ʿUmar ibn al-Khattab ﵁ after the dismissal of Khalid ﵁ as overall field commander. But in tactical decision-making Abu ʿUbayda ﵁ relied on Khalid ﵁‘s acumen for the open field. When the army reached the southern fringe of the plateau, Khalid ﵁ called the commanders together and gave them time to study the Byzantines’ advantage of height.

Scouts rode ahead to Ayn Dhakar, the spring and fordable crossing that would define the western flank of the battlefield. Others crept along Wadi al-Allah to probe the Byzantine eastern flank. The reports came in toward nightfall. The Byzantine camp lay on the northern heights, with heavy infantry in the center, Armenian and Slavic contingents on the wings, and cavalry behind the main line. Heraclius himself was not present; command rested with Vahan, the Armenian general, with Theodorus and Buccinator under him.

Khalid ﵁ divided his army into four corps along the southern edge. Yazid ibn Abi Sufyan ﵁ on the east wing, Shurahbil ibn Hasana ﵁ in the center-right, ʿAmr ibn al-ʿAs ﵁ in the center-left, and Abu ʿUbayda ﵁ with the Muhajirun at the heart of the line. Khalid ﵁ himself kept the mobile cavalry reserve back, ready to strike wherever needed.

At the evening salat the Sahabah ﵃ prayed behind Abu ʿUbayda ﵁. Then the camp withdrew into silence. The wadis on both sides remained unguarded by the Byzantines, who assumed the Arabs would seek the open plain. Khalid ﵁ noted that. In the days that followed he would turn that knowledge into a trap.

On the second day of the engagement Vahan set his right wing in motion. He hoped to envelop the Muslim left flank by wheeling his cavalry westward past Ayn Dhakar, and from there strike the Muslim rear. It was a conventional maneuver, proven on the Danube frontier against Avars and Slavs, and it assumed the adversary would not move before the pincer closed.

Khalid ﵁ let the Byzantine cavalry describe its first arc, then sent the order to the Muslim center to withdraw slowly in the direction of Ayn Dhakar. It was not a flight. It was a choreography. The center fell back step by step, raising and waving its banners as an army does when it regroups, not as an army does when it breaks. But from a distance Vahan saw a retreat, and the Byzantine cavalry was ordered to take up the pursuit.

On the flanks the Muslim wings pivoted. Yazid ibn Abi Sufyan ﵁ on the east wing did not fall back; he turned slowly northward, so that his wing formed an angle with the center. ʿAmr ibn al-ʿAs ﵁ did the same on the western side, closer to the wadi. The Byzantine right wing, intent on the pursuit, did not see the pivot coming.

By the time the Byzantine cavalry reached the center, Khalid ﵁'s reserve was already in motion. He sent Dirar ibn al-Azwar ﵁ with a light cavalry group westward to occupy the northern rims of Wadi al-Ruqqad. The way back for the pursuit would thereby be barred, without the pursuers realizing it.

At nightfall Khalid ﵁ called the commanders together under the palm trees at the southern edge of the plateau. “Tomorrow,” he said, “we wear them down until they can no longer find their own wadis.” The banners were planted for the night; the watches were doubled; the horses were watered at Ayn Dhakar under protected escort.

On the third day the Byzantine cavalry completed the trap into which Vahan had unwittingly sent it. The previous day’s pursuit had drawn them far to the southwest, and the way back over the wadi rim of Wadi al-Ruqqad proved barred. Dirar ibn al-Azwar ﵁ had occupied the northern routes above Ayn Dhakar, and his archers loosed volleys at the Byzantine rearguard.

Khalid ﵁ sent his light cavalry along the plateau rim to drive the Byzantine cavalry further northward, toward the ravine of Wadi al-Allah on the eastern side. The wadis no longer formed a flank cover but a prison. Whoever tried to flee from the plateau fell into the gorge. Whoever tried to hold at the edge was shot from above by Muslim archers.

The Byzantine field commander of the right wing tried to rally at the wadi’s edge. He brought his riders into a horseshoe formation and hoped for a breakout to the northern heights. But the Muslim cavalry under al-Qaʿqaʿ ibn ʿAmr ﵁ came from two sides, and the Byzantine formation was broken before it was complete. Heavy losses were suffered in the flight to Wadi al-Allah; hundreds of riders fell into the gorge with their horses, and their bodies covered the wadi floor.

In the afternoon Khalid ﵁ stood on the southern rim of Wadi al-Ruqqad and watched the last Byzantine cavalry units fall apart. He ordered the pursuit halted. “Let them flee to Vahan,” he said. “He has already given them up.” The Muslim archers withdrew from the wadi rim, and the cavalry regrouped for the evening salat.

In the Byzantine main camp that evening a shaken officer reported to Vahan that his right wing had been shattered, and that the Arab cavalry was using the wadis as a trap in a way that stood in no manual. Vahan would answer the next day with his main infantry.

On the fourth day Vahan brought his main infantry southward. The cavalry losses of the previous days were unmistakable, but the Byzantine heavy infantry still consisted largely of unscathed units. The Armenian, Slavic and Greek contingents together formed a wall four or five ranks deep, with shields locked and spears leveled. For such a line, Heraclius’ field manual prescribed a slow, methodical advance in lockstep.

Khalid ﵁ had his center under Abu ʿUbayda ﵁ hold its ground. He sent the archers of the Banu Quraysh forward, and the Muslim front line received the Byzantine advance with a continuous volley. The wall absorbed a first rain of arrows, but the ranks in the third and fourth row began to waver. A small advantage, but it opened the possibility for what Khalid ﵁ had been saving.

He gave the signal to Yazid ibn Abi Sufyan ﵁. From the eastern flank, along Wadi al-Allah, Yazid ﵁'s cavalry came in an oblique charge against the Byzantine right wing. The right wing had not yet replaced the cavalry losses of the previous day, and the infantry on that side stood without mounted cover. The cavalry charge broke through the shield line in under a minute.

In the center Khalid ﵁ committed as well. He sent the heavy Muslim cavalry behind the Banu Quraysh archers forward in a focused thrust against the Byzantine heart. Hand-to-hand fighting erupted along a front nearly two kilometers wide. The Armenian center troops held out long. The Greek right wing began to give way as soon as Yazid ﵁'s cavalry was through the first rank.

By late afternoon the Byzantine center line had split itself in two. The left half tried to withdraw steadfastly to the northern heights. The right half was broken and plunged into chaotic flight toward Wadi al-Allah, where they were hunted down by Yazid ﵁'s riders.

Khalid ﵁ rode along the front of the Muslim line himself and heartened the commanders. “It is no longer a fleeing army,” he said. “It is a shattered army. Tomorrow we close.”

On the fifth day the Byzantine left flank collapsed. The pressure of Muslim cavalry and archers had kept grinding on through the evening; in the morning air only about three thousand Byzantine cavalry riders of the left flank were still standing, and their ranks were crumbling with exhaustion. Khalid ﵁ opted for a combined assault. Archers loosed aimed volleys, and the Muslim cavalry gathered at the northwest corner for the breakthrough.

The Byzantine left flank broke in less than an hour. What remained withdrew northeastward, toward the Yarmuk-Jordan confluence, hoping for a return to Syria by the northern route. Khalid ﵁ directed the pursuit himself. He ordered ʿIyad ibn Ghanm ﵁ to ride with a light cavalry group parallel to the Byzantine escape route, to cut them off from their final point of escape.

The confluence of the Yarmuk and the Jordan, some fifteen kilometers to the northwest, was a natural trap. High rock walls along the Jordan side made passage for cavalry impossible; the Yarmuk side ran dead into a shallow marshland. Whoever reached the confluence could no longer flee to Syria, but had to stand and fight or drown in the marshes.

Khalid ﵁ repositioned himself to the northeast, to a point from which he could survey the entire rout. From that position he watched the Byzantine retreat stretch out over kilometers, with fragments of units that had lost all discipline. ʿIyad ﵁'s cavalry closed the trap south of the confluence.

By late afternoon the Muslim force had destroyed the greater part of the Byzantine left flank, or penned it in terrain without an escape route. The next day would bring no escape for the rest of the Byzantine army.

On the sixth day the Byzantine center lost its cohesion. The pressure of Muslim cavalry on all three flanks, the exhaustion of six days of unbroken fighting, and the sight of the wadis as three open pits around the battlefield broke the morale of even the most disciplined Armenian units. Vahan attempted one last rally at his command tent, but his officers could no longer keep the ranks standing.

Khalid ﵁ committed his entire cavalry reserve for the final assault. Six corps came simultaneously from six different directions, like the spokes of a wheel converging on the hub. The Byzantine army was cut to pieces. The fragments that did not fall fled in all directions, and the three wadis received the greater part of them. Wadi al-Yarmuk, Wadi al-Ruqqad and Wadi al-Allah were described in the traditions as death traps, with thousands of bodies on the wadi floor.

Some Byzantine units under Buccinator managed to fight their way northward out of the battlefield, along a narrow path the Muslim pursuit had not cut off. They vanished in the direction of Damascus and Hims. The rest of the army was either killed or taken prisoner. Estimates of the number of Byzantine dead vary widely. Tabari gives up to one hundred and twenty thousand; lower estimates speak of twenty to forty thousand, which was still a destruction without precedent in the Byzantine seventh century. Muslim losses were given as about four thousand Sahabah ﵃, among them eighty veterans who had fought side by side with the Prophet ﷺ at Badr and Uhud.

Vahan himself vanished from the battlefield; the sources differ on his fate. Some say he fell in the general rout; others that he withdrew to a monastery in northern Syria. Heraclius, when the news reached him in Antioch, spoke the words recorded in every later chronicle: “Farewell Syria, my fair province. Farewell.”

With Yarmuk, Bilad ash-Sham lay open to Islam. Khalid ﵁ rested two days on the battlefield, had the wounded tended, the dead buried, and the khums sent to Medina. Then Abu ʿUbayda ﵁ marched northward to Damascus, which fell within two months without serious resistance.