The future Emperor Leo III of Constantinople (r. 717-741) was born near what is now Kahramanmaraş, Türkiye, and heralded from the Isaurian stock of south-central Anatolia (hence the name of the Isaurian Dynasty he founded). and his family was relocated to Thracian Mesembria during the first reign of Emperor Justinian II of Constantinople (r. 685-695). Leo’s childhood and young adulthood remain relatively obscure, but according to the chronicler Theophanes (750s-818), Leo and his family did well for themselves in Mesembria, acquiring wealth and influence. During the time when Emperor Justinian II was subsequently displaced by Leontios (r. 695-698) and then Tiberius III (r. 698-705), Leo grew to possess the prestige required to gain an audience with emperors, and he had the means to throw material support behind factions of his choosing. Consequently, when Justinian II later returned (with Bulgarian allies) to seize back his throne from the usurpers in 705, young Leo was able to raise imperial eyebrows by allegedly donating 500 sheep to Justinian’s war effort. Impressed by the gesture, Justinian II granted Leo the title of spatharios (or sword-bearer) and recruited him to serve as one of his officers. On this, Theophanes wrote, “When Justinian came there with the Bulgars during his second reign, Leo met him with a gift of five hundred sheep. Flattered, Justinian made him a spatharios on the spot and judged him a true friend” (Theophanes, Chronographia, entry for Annus Mundi 6209). After that fortuitous meeting, Leo was reportedly dispatched by Emperor Justinian II (r. 685-695, 705-711) to the Caucasus region, where he was involved in supporting the Byzantine-aligned Alans (or Alani) against the Arab-allied Abasgians.
Leo’s adventures in Abasgia were a complex and complicated saga, and there is difficulty discerning the true history from the encompassing folklore and legend of that period. Nonetheless, according to the narrative told by the chronicler Theophanes, Leo and the Alans concocted a plan to trick the Abasgians into believing that the Alans would betray Leo and the empire. The scheme, so the story goes, was for Leo to be handed over to the Abasgians as a sign of good will and partnership, after which the Alans (on the pretense of now being an Abasgian ally) would clandestinely scout out the lands and defenses of Abasgia. Prompt in their scouting, the Alans were able to ambush the Abasgian convoy that was transporting Leo, and they successfully freed him before he could be moved to a secure location. On the trickery and the surprise assault, Theophanes wrote: “The Abasgians’ envoys took the spatharios and his men, bound them, and went off. The Alans and their lord Itaxes overtook the Abasgians from behind; they killed them and hid Leo. Once they had levied troops, they marched on Abasgia and unexpectedly penetrated its passes. They took a great number of prisoners and worked destruction on the Abasgians” (Chronographia, entry for Annus Mundi 6209). Suffice it to say, the Alan war against Abasgia went extremely well. But the recognition that Leo gained from his involvement in the campaign came at a price, because Emperor Justinian II was a paranoid man who grew increasingly tyrannical after all of the betrayals he faced in his troubled life. Leo, sensing that his successes and popularity might make him a target of the suspicious emperor, allegedly began surveying the region for safe havens.
Around the same time when Leo was involved in the Abasgian campaign, Emperor Justinian II had also reportedly dispatched some troops to assault Arab positions in Lazica (the eastern coastlands of the Black Sea region, approximately the western half of the modern country of Georgia). Whereas the Alan campaign against Abasgia had gone well, the raids against Lazica played out abysmally, and as a result of the chaos, around 200 members of the dispatched force became caught in the nearby Caucasus Mountains, where they sustained themselves through banditry. Refocusing on Leo, when he learned he was at risk of becoming a target of Emperor Justinian’s suspicion and paranoia, it was to this band of mountain-dwelling brigands that Leo reportedly turned.
Disregarding instructions from Emperor Justinian II to return home through Abasgia, Leo and some Alan guides instead reportedly trekked over the Caucasus Mountains to find the camp of the 200 stranded warriors. As told by Theophanes, Leo “took fifty Alans and crossed the peaks of the Caucasus with snowshoes (in May!). He found the men and joyfully asked them, ‘Where is your army?’” (Chronographia, entry for Annus Mundi 6209). There, with that band of rugged mountaineers, Leo’s alleged adventures became even more grandiose.
Leo, after reportedly placing himself in command of the troops of the mountain camp, set his eye on a nearby Arab-aligned fortified position called Sideron. There, a commander named Pharasmanios, led a garrison that manned a formidable fortress. As the story goes, Leo and his small army laid siege to Sideron, and managed to do so in a way that never revealed their small numbers. At that same time, Leo reportedly made contact with a leader named Marinos, from Apsilia (another land from the eastern Black Sea region of Lazica), and recruited him as an ally. Although Marinos, at first, was also kept unaware of Leo’s manpower shortage, the Apsilian turned out to be a great partner in Leo’s time of need.
Marinos brought troops to reinforce Leo’s difficult siege of Sideron, and Marinos’ presence reportedly convinced Pharasmanios to surrender the fortress. Yet, Leo had no intention of occupying the fort with his meagre band of warriors. Instead, he reportedly decided to burn the place to the ground and then withdrew with his new friend, Marinos, to Apsilia. From there, Leo was able to assess the mood of Emperor Justinian II and orchestrated for himself a relatively safe reintroduction to the imperial court of Constantinople. On these events, Theophanes wrote, “he ordered the citadel [of Sideron] set afire. There was a great conflagration; the families came out, snatching up whatever they could of their property. After they spent another three days there, the troops razed the fort’s walls to the ground. With the Apsilian leader Marinos they went to Apsilia, where the Apsilians received them with great honor. From there Leo went to the coast, crossed, and went to Justinian” (Theophanes, Chronographia, entry for Annus Mundi 6209).
Despite Leo’s earlier fears about Justinian II, the returned officer faced no known punishment, harassment or legal issues from the emperor. The only sign that Justinian II may have been displeased with Leo was the poignant absence of any new tasks or appointments of note given to him by the emperor. Ironically, this could have been a blessing, as Leo was able to remain safely out of sight and mind during the chaotic time when Emperor Justinian II was subsequently overthrown by the rebel, Philippikos (r. 711-713), whose power was then usurped by Emperor Anastasius II (r. 713-715). It was the latter ruler, Anastasius II, who brought Leo back to the forefront of leadership, appointing him as the military leader and governor (or strategos) of the empire’s Anatolic region (or theme). This point in the narrative, it should be noted, is when Theophanes’s account of Leo’s origin starts to become truly verifiable and cross-checkable.
Upon his appointment as a governor in Anatolia, Leo was loyal to Emperor Anastasius II, but the ruler was soon ousted by a rebellion that put Emperor Theodosios III (r. 715-717) on the throne. Leo refused to recognize Theodosios as a legitimate ruler and immediately launched a rebellion of his own. Leo also enticed his son-in-law, Artavasdos (strategos of the Armeniac Theme), to join him in the revolt. The timing of their rebellion could not have been better, for it occurred at a moment when Umayyad Arab incursions into the imperial realm of Constantinople were increasing in intensity, placing Emperor Theodosios III and his lands in real peril. The rebels and the Arabs had a tense truce, and Leo and the leaders of the nearby invading armies frequently exchanged correspondence. Yet, the rebel general feared being captured and exploited as a puppet by the Arabs, so he remained wary in his movements and tried to keep his distance from the Umayyad forces. Leo, avoiding Arab armies and loyalist forces of Theodosios, was able to weave his way to the city of Nikomedeia, where he reportedly managed to capture the emperor’s son. Leveraging this abduction, Leo convinced Theodosios III to renounce his claim to the throne, as well as that of his son, and abdicate in favor of Leo. On this, Theophanes wrote:
“…Leo went to Nikomedeia. He met Theodosios’ son and captured him, the entire imperial retinue, and the palace’s leading figures. The general took counsel with his men; he took the Emperor’s son to Chrysopolis as a prisoner…When Theodosios learned what had happened he consulted the patriarch Germanos and the senate. Through the patriarch he received a pledge from Leo that he would not be harmed and that the church would not be disturbed, and on those terms entrusted the Empire to him. Theodosios and his son became clerics, and lived out the rest of their lives in peace” (Theophanes, Chronographia, entry for Annus Mundi 6208 [Sep 715-Aug716]).
Thus, Emperor Leo III (r. 717-741) assumed the throne, ushering in the Isaurian Dynasty that would dominate Constantinople for the rest of the century. Dynastic legacy aside, the inaugural years of Leo’s reign would be a challenge, as the Arab forces in the region converged on Constantinople to besiege the imperial city between 717-718. Using Constantinople’s formidable Greek Fire, the imperial navy was able to break through the siege just in time to confront and suppress a rebellion that broke out in Italy. The rebellion was thwarted and the conspirators were rounded up by 719, earning Leo and his empire some much-needed peace and stability. Leo’s path to power was truly a raucous and chaotic rise to the top.
Written by C. Keith Hansley
Picture Attribution: (Tremissis (Coin) of Leo III, dated between 720–741, [Public Domain] via the Art Institute of Chicago).
Sources:
- Theophanes, The Chronicle of Theophanes, translated by Harry Turtledove. Philadelphia: University of Pennsylvania Press, 1982.
- The Oxford Dictionary of Late Antiquity, edited by Oliver Nicholson. Oxford: Oxford University Press, 2018.
- https://www.britannica.com/biography/Leo-III


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