The major religions of Europe and north africa in 1100 in the world of the map I recently posted.
After the successful invasion of Anatolia by the Abbasids from 1105-1117 the state of the Byzantine Empire is heavily weakened. Without any substantial natural border to the east the empire falls into disarray. The overthrow of the Gaznavids in 1121 by the Karakalpaks. The new Persian dynasty ended nearly a century of peace with the Abassids and sacked the city of Baghdad in 1123 forcing the Arab armies out of Anatolia to defend the heart of the empire.
John the Athenian became emperor in 1119 in a coup overthrowing the unpopular Constantine IX. Civil unrest ensued as the Anatolian generals vied for power, many hoping to gain independence or take the empire for themselves. Basileus John was only narrowly able to prevent outright civil war. in 1125 he seized Venetian and Bulgarian goods and ships in Constantinople in order to establish a fleet and pay the armies. Nearly 13,000 Venetians and Bulgarians were imprisoned, mostly in Constantinople. John hoped to be able to ransom them back in order to get the empire out of debt. By doing this he was able to bring the Anatolian provinces back under control. An alliance with Genoa was established in 1127 further strengthening his position. He believed this alliance would deter retribution by the Bulgars and Venetians. He began to prepare for a war against the Abbasids. However, this would not occur as in 1129 an alliance between Venice and Bulgaria would invade in order to free their citizens imprisoned and recoup their losses. John was by all respects a masterful general and he was able to repel the Bulgarian army before they were able to lay siege to the capital. In response the Bulgarian armies withdrew west and took Epirus. In the battle of Ionia the only significant Byzantine army in Greece was routed and withdrew to Athens.
At sea the Venetians were able to defeat the Genoan and Byzantine fleets in the battle of Ithaca in 1130. The Venetian armies blockaded Ithaca and Zante while their armies took Morea without much resistance.
Even though most of Greece had been taken John's army was still very much intact but could not leave Thrace as it would leave Constantinople undefended. He sent what reinforcements he could to the forces in Athens who attempted to catch the Bulgarian by surprise. The army crossed the Aoos and met the Bulgarian army south of Prilep. The battle was a failure and most of the army was captured. In late 1134 John received news of the defeat and surrendered. In 1135 the Treaty of Venice was signed giving much of Greece to the Bulgarians and Venetians. John was removed as emperor but was allowed to continue to rule as the despotate of Athens. Genoa was forced to surrender the Ionian islands to Venice. Emperor Peter II of Bulgaria attempted to put his brother on the Byzantine crown however objections by the Venetians the Mesopotamitai dynasty was put into power and Theodore Mesopotamites was crowned emperor and was married to the daughter of Peter II, Mariika.
As a result of this war the Bulgarian empire was indisputably the pre-eminent orthodox power in Europe. The Duchy of Tarantino began to grow closer to the Bulgarians than the Byzantines as they were now much too weak to offer any protection. The Duke ceased to pay tributary to the Byzantines in 1138. As a result of this Europe began to grow weary of the Bulgarian power. This tension would soon come to a head.
After the successful invasion of Anatolia by the Abbasids from 1105-1117 the state of the Byzantine Empire is heavily weakened. Without any substantial natural border to the east the empire falls into disarray. The overthrow of the Gaznavids in 1121 by the Karakalpaks. The new Persian dynasty ended nearly a century of peace with the Abassids and sacked the city of Baghdad in 1123 forcing the Arab armies out of Anatolia to defend the heart of the empire.
John the Athenian became emperor in 1119 in a coup overthrowing the unpopular Constantine IX. Civil unrest ensued as the Anatolian generals vied for power, many hoping to gain independence or take the empire for themselves. Basileus John was only narrowly able to prevent outright civil war. in 1125 he seized Venetian and Bulgarian goods and ships in Constantinople in order to establish a fleet and pay the armies. Nearly 13,000 Venetians and Bulgarians were imprisoned, mostly in Constantinople. John hoped to be able to ransom them back in order to get the empire out of debt. By doing this he was able to bring the Anatolian provinces back under control. An alliance with Genoa was established in 1127 further strengthening his position. He believed this alliance would deter retribution by the Bulgars and Venetians. He began to prepare for a war against the Abbasids. However, this would not occur as in 1129 an alliance between Venice and Bulgaria would invade in order to free their citizens imprisoned and recoup their losses. John was by all respects a masterful general and he was able to repel the Bulgarian army before they were able to lay siege to the capital. In response the Bulgarian armies withdrew west and took Epirus. In the battle of Ionia the only significant Byzantine army in Greece was routed and withdrew to Athens.
At sea the Venetians were able to defeat the Genoan and Byzantine fleets in the battle of Ithaca in 1130. The Venetian armies blockaded Ithaca and Zante while their armies took Morea without much resistance.
Even though most of Greece had been taken John's army was still very much intact but could not leave Thrace as it would leave Constantinople undefended. He sent what reinforcements he could to the forces in Athens who attempted to catch the Bulgarian by surprise. The army crossed the Aoos and met the Bulgarian army south of Prilep. The battle was a failure and most of the army was captured. In late 1134 John received news of the defeat and surrendered. In 1135 the Treaty of Venice was signed giving much of Greece to the Bulgarians and Venetians. John was removed as emperor but was allowed to continue to rule as the despotate of Athens. Genoa was forced to surrender the Ionian islands to Venice. Emperor Peter II of Bulgaria attempted to put his brother on the Byzantine crown however objections by the Venetians the Mesopotamitai dynasty was put into power and Theodore Mesopotamites was crowned emperor and was married to the daughter of Peter II, Mariika.
As a result of this war the Bulgarian empire was indisputably the pre-eminent orthodox power in Europe. The Duchy of Tarantino began to grow closer to the Bulgarians than the Byzantines as they were now much too weak to offer any protection. The Duke ceased to pay tributary to the Byzantines in 1138. As a result of this Europe began to grow weary of the Bulgarian power. This tension would soon come to a head.
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