By the mid-7th century, the Eastern Roman, or Byzantine, Empire faced an existential threat unlike any before: the relentless and sweeping conquests of the nascent Arab Caliphate. What began as raids had transformed into a rapid expansion that stripped Byzantium of its wealthiest provinces, including Syria, Egypt, and parts of North Africa. Emperor Constans II, grandson of Heraclius, inherited an empire in crisis, constantly battling on multiple fronts. His reign was marked by desperate attempts to stem the tide, but also by pragmatic decisions born of necessity. It was in this dire atmosphere that the Arab-Byzantine Treaty 659 was forged, a pivotal diplomatic agreement that offered a much-needed, albeit temporary, respite to the beleaguered empire, allowing Constans II to refocus his considerable energies on other pressing internal and external challenges.
The Empire Under Siege: The Relentless Arab Advance
Following the death of the Prophet Muhammad, the Islamic armies burst forth from Arabia, quickly overwhelming the Sassanian Persian Empire and then turning their formidable attention to Byzantium. The empire, already exhausted by decades of war with Persia, proved vulnerable. One by one, major provinces fell: Damascus in 635 AD, Jerusalem in 637 AD, and the entirety of Egypt by 642 AD. The loss of these territories not only deprived the empire of crucial tax revenues and manpower but also dramatically altered its strategic outlook. The Arabs, under leaders like Mu’awiya, rapidly developed a powerful navy, challenging Byzantine supremacy in the Mediterranean and launching devastating raids on imperial territories, including Cyprus and Rhodes. Constans II, who ascended the throne in 641 AD, found himself at the helm of a fragmented and beleaguered state, constantly on the defensive against an enemy that seemed unstoppable.
Naval Dominance and Constant Pressure
The Arab victory at the Battle of the Masts in 655 AD, where the Byzantine fleet was decisively defeated, underscored the gravity of the situation. This naval catastrophe opened the Aegean Sea and the approaches to Constantinople itself to Arab incursions. The empire was fighting for survival, with its very heartland threatened. The continuous pressure meant resources were stretched thin, and the logistical challenges of defending a vast, shrinking frontier were immense. Constans II understood that a sustained, two-front war against both the Arabs and other adversaries in the West was simply unsustainable.
Constans II’s Strategic Retreat and Diplomatic Overtures
Facing the immediate and overwhelming threat from the rapidly expanding Caliphate, Emperor Constans II made a pragmatic, if difficult, decision: to seek a temporary peace with his eastern adversaries. This was not a surrender, but a strategic pause designed to give the empire breathing room. His intention was to stabilize the eastern frontier, however briefly, so he could address other urgent issues, particularly in the West, where the Lombards were a growing menace in Italy.
The Terms of the Treaty
Negotiations were initiated with the Caliph Mu’awiya I, then the governor of Syria and soon to be the first Caliph of the Umayyad dynasty. The resulting Arab-Byzantine Treaty 659 stipulated several key conditions:
- Annual Tribute: The Byzantine Empire agreed to pay a substantial annual tribute to the Caliphate. This payment was a clear acknowledgment of Arab military superiority and a bitter pill for the Byzantines to swallow.
- Cessation of Hostilities: Both sides agreed to a ceasefire, bringing a halt to the incessant raiding and warfare that had plagued the borders for years.
- Military Cooperation (Disputed): Some historical sources suggest that the treaty might have included a clause for mutual military assistance, particularly against common enemies or internal rebels. However, the precise nature and extent of this cooperation remain a subject of academic debate.
The terms were certainly humbling for the once-mighty Roman Empire, but they provided a crucial reprieve. Constans II understood that prolonging a losing fight on the eastern frontier would only hasten the empire’s demise. The treaty, therefore, represented a calculated strategic withdrawal rather than a defeat.
Consequences and Legacy of the Treaty
The peace secured by the Arab-Byzantine Treaty 659, though costly in prestige and resources, had profound short-term consequences for the Byzantine Empire. It allowed Constans II to turn his attention westward. In 660 AD, just a year after the treaty, he famously moved his court to Syracuse in Sicily, establishing a new power base from which he hoped to reorganize imperial defenses and campaign against the Lombards in Italy. This bold, almost unprecedented, move highlighted his determination to preserve the Roman legacy in the West, even if it meant temporarily ceding the initiative in the East.
A Fleeting Respite and Lasting Precedent
The peace, however, was destined to be short-lived. The internal strife within the Caliphate (the First Fitna or civil war) that had prompted Mu’awiya to seek the treaty eventually subsided. With his position consolidated, Mu’awiya renewed the aggressive expansionist policies, and by 663 AD, the peace was effectively over. Despite its brevity, the 659 treaty set a significant precedent for future Arab-Byzantine relations. It demonstrated that diplomatic solutions, even those involving tribute, could offer a temporary cessation of hostilities. This pattern of truces, broken by renewed warfare, would characterize the frontier for centuries, allowing both empires to manage resources and regroup during periods of relative calm. For Constans II, it bought precious time, though ultimately, his ambitious western campaigns would end tragically with his assassination in 668 AD, leaving a complex legacy for his successors to navigate.
Frequently Asked Questions
What was the primary reason for the Arab-Byzantine Treaty of 659 AD?
The primary reason was the ongoing civil war within the Arab Caliphate (the First Fitna), which made Caliph Mu’awiya seek a temporary peace to consolidate his power. For the Byzantines under Constans II, it offered a crucial respite from the relentless Arab expansion, allowing the Emperor to address other threats and internal issues.
Who were the key figures involved in negotiating the 659 AD treaty?
The key figures were Byzantine Emperor Constans II and the Arab leader (and future Umayyad Caliph) Mu’awiya I, who at the time was the governor of Syria and a claimant to the Caliphate.
What were the main terms of the peace agreement?
The main terms of the Arab-Byzantine Treaty 659 included the Byzantine Empire paying an annual tribute to the Caliphate and a cessation of military hostilities between the two powers. Some sources also suggest possible clauses for mutual military assistance.
How long did the peace established by the treaty last?
The peace established by the 659 AD treaty was relatively short-lived. It lasted only a few years, with hostilities largely resuming by 663 AD once Mu’awiya had consolidated his control over the Caliphate.
What was Constans II’s strategy after securing peace with the Arabs?
After securing the Arab-Byzantine Treaty 659, Constans II shifted his strategic focus to the West. He moved his court to Syracuse in Sicily in 660 AD, intending to reorganize imperial defenses and campaign against the Lombards in Italy, hoping to preserve Byzantine influence in the region.
