The Byzantine Empire was central to all of these events, but we often overlook their role in the Crusader kingdoms since the Franks were so often opposed to the Greeks. The Crusaders acted alone most of the time, after the initial invasion was over.
The Emperor who wrote to the Pope back in the 1090’s was Alexios, who remained the ruler throughout the early Crusader kingdom years. Alexios died in 1118, around the time the Knights Templars were established, during the reign of Baldwin II.
His son John had two older sisters (Anna is famous for having taken notes on the Crusaders), and as it so often went in Constantinople, his succession was not simple or assured. His mother Empress Irene preferred Anna’s husband, a powerful general, over her own sons. But John stole his dying father’s ring and proclaimed himself Emperor John II in public, winning support from the city mob. His sister Anna’s history-writing seems to have been prompted by her surplus of free time after she and her husband were exiled.
John II is remembered as The Good or Beautiful (ό καλος). He was very pious, and he set out to reverse Byzantium’s recent losses. First he married the Hungarian princess Piroska, renaming her “Irene” after his mother. They had eight children. He reconquered the Balkans and even his wife’s homeland of Hungary. He set out across Anatolia, putting the Turks on the defensive at last. He was never able to push the Danishmend Turks out of the northeast, but he regained control over many other provinces.
The Crusaders sometimes allied with him against Muslim Syria, but as always, they were very ambivalent about the Greek Emperor. In 1142, John announced to King Fulk that he intended to go on a “pilgrimage” to Jerusalem with several hundred of his closest armed friends. Fulk replied that he’d love to have them, but the land around Jerusalem was just so dry, the economy so poor, etc., he really thought that the retinue should be restricted to maybe a dozen. John lost interest, not willing to go into full war.
John’s best friend and vizier was a Turkish boy captured at the siege of Nicaea, back at the start of the First Crusade. They grew up together, though the Turkish boy may have technically been his slave. In this period, with Mamluks ruling cities, slave and friend were not always rigid distinctions. We see this pattern often, later, in Ottoman Sultans who adopted and promoted a slave best friend.
John’s last acts were an attempt to take back both Edessa and Antioch, which Byzantium had never conceded to the Crusaders. He died in Cilicia in a hunting accident, while he was preparing to besiege Antioch.
John had two surviving sons, the older Isaac and the younger Manuel, and he chose Manuel to become Emperor, stating the Isaac was not fit by temperament. John’s Turkish best friend/vizier helped by leaving the deathbed quickly to arrest older son Isaac in Constantinople. When Manuel was proclaimed Emperor there, he decided to release brother Isaac, but he took the extra safety measure of dipping into the royal treasury to give every house-owner two gold pieces. The city’s citizenry (sometimes known as a mob) was usually the deciding factor in succession.
In the early years, Emperor Manuel looked like he could restore the lost glory of Byzantium. He is remembered as Manuel the Great (ὁ μέγας).
The Crusader Prince of Antioch had to seek help from Manuel after Edessa fell in 1144, so within these first years, Manuel’s influence extended to the very cities his father had wanted back. The German king formed an alliance with Manuel, sealed by sending his queen’s sister to marry the Emperor. Her name was Bertha, but she had to be re-baptized in the Greek rites with a new name. As usual, she was now called Irene, the third Empress Irene in a row. There’s some record that she found the luxury and decadence of Constantinople as a moral shock and never quite adjusted.
This was the period when the Second Crusade ran its course. Germany and Byzantium were allies to keep the Normans of Sicily from assaulting Greece and Albania again. They also worked together to try to win back Edessa from Zengi’s son Nur ad-Din. Manuel achieved a lot, winning back much territory….but in the end, it didn’t really matter. He’ll show up in Second and Third Crusade stories, and after his queen’s death he also married into the “Real Housewives of Outremer” drama of Baldwin’s daughters. But the Turks were on the ascendant and their momentum could only be checked for a short time.
The Komnenoi left another footnote: one of John’s sisters had a son, also John, who converted to Islam and married the Sultan’s daughter. The Sultan probably planned an invasion with this nephew at its head, but it didn’t happen. However, the Ottoman line claims descent from this couple, probably to make their takeover more palatable.