A capital between two seas
The Byzantine Empire’s strength owed a great deal to location. Constantinople sits on the Bosporus, the narrow strait that links the Black Sea to the Sea of Marmara and then the Aegean. Ships moving between those seas had to pass beside the city, and land routes between Europe and Asia converged there. The empire usually had enemies on several sides at once, but it also had access to a large share of the trade of the eastern Mediterranean.
Diplomacy as a main tool
Byzantine rulers generally preferred to manage threats with diplomacy when they could. Their army was costly and not always available, so the court developed a variety of techniques for influencing neighbors:
- Titles and gifts. Foreign rulers were granted court ranks and sometimes yearly payments, along with silks and ceremonial objects. This tied them to the empire in a ranked order, with the emperor at the top.
- Marriage. Imperial family marriages with foreign rulers were used selectively. Court writers were often reluctant to marry imperial daughters to foreigners, but there were exceptions.
- Religion. Missionary work introduced Orthodox Christianity to the Slavs and others, often strengthening ties of influence.
- Information. A tenth-century handbook attributed to Emperor Constantine VII, written to guide his son, describes the habits and politics of many neighboring peoples and recommends playing them against each other. It reflects a court that collected information carefully.
- Ceremony. Receptions in the palace were staged to impress visitors with the empire’s wealth and order. A western envoy, Liudprand of Cremona, left a famous and rather hostile account of his visit in the 960s.
This did not replace fighting. Byzantine commanders often wrote manuals on avoiding pitched battle when odds were poor, and on using raids, ambushes and local allies. But the court’s habit was to treat force and persuasion as parts of the same toolbox.
Persians, Arabs and Turks
The empire’s neighbors changed over the centuries. In the early period, the great rival was Sasanian Persia, and the two powers fought repeatedly over Armenia, Mesopotamia and Syria. A final long war in the early 600s left both exhausted.
Arab armies then took Syria and Egypt in the 630s and 640s, and the Byzantines never regained them. The caliphates became the main rival for several centuries, and the frontier in southeastern Anatolia was a zone of regular raids on both sides, with fortified outposts and some border commanders who became almost independent. Struggles with the Abbasid caliphate included exchanges of prisoners as well as warfare. The empire went on the offensive in the 900s and recovered land in northern Syria for a time.
A new danger came with the Seljuk Turks. The Battle of Manzikert in 1071 led to a loss of central Anatolia, and Turkish principalities later formed across the interior. Eventually the early Ottoman state grew out of this world of frontier principalities, and its Ottoman expansion would decide the empire’s fate.
Steppe peoples and the north
The empire also faced peoples to the north: Avars, Bulgars, Magyars, Pechenegs and others. Each time, Byzantine policy mixed payments, alliances and campaigns. Bulgaria was the longest-lasting problem, and the contest ended for a time with Basil II’s conquest around 1018. The Rus of Kyiv, who first appeared as raiders and traders, were drawn into the empire’s circle through baptism and military service.
The navy and the sea
A navy was vital to an empire so exposed to the sea. Byzantine warships were typically oared galleys, called dromons, and the fleets ran supply lines, defended the coasts and fought Arab naval forces. The best-known weapon was the incendiary substance known as Greek fire, which was sprayed from tubes on ships. Its exact composition is uncertain; it was treated as a state secret.
In the 1100s the fleet was reduced, and the empire turned to Venice and other Italian cities for naval help. This provided short-term security but led to long-term dependence on the Venetian republic and its rivals.
Trade and money
Constantinople’s market served as a hub between the Black Sea, the Balkans, the Mediterranean and caravan routes from the east. The empire controlled the trade in silk, with government workshops and rules limiting what could be sold abroad. Its gold coin, which kept a stable reputation for centuries, was accepted well beyond its borders.
Italian merchants gradually gained a larger share. Venice received tax advantages in the late 1000s, a grant traditionally linked to a document of 1082, and Genoese merchants and others followed. Over time these privileges cut into imperial revenue and caused resentment, and they were one of several factors that left the empire weaker economically. Not all historians agree on how much damage this did.
Place in a changing region
By the 1200s the eastern Mediterranean was shared among many powers: the Crusader States, Ayyubid and Mamluk rulers, Seljuk and later Ottoman states, Italian maritime cities and the Mongols on the horizon. The Byzantine Empire had gone from being the dominant regional power to being one participant among several. Its use of negotiation, marriage and reputation stayed the same, but it had far fewer resources to back them up.