Brutal power plays

Lothar or Lothair III, Holy Roman Emperor (reigned 1133-1137)

1136. While John II Komnenos pushed east, his allies in the west went into action against the Normans of Sicily. The army of Pisa sacked Amalfi, and from late 1136 the German emperor, Lothar III, led an expedition into southern Italy. There he lifted the siege of Naples and conquered much of Apulia, including Bari. 

Lothar probably had assistance from John, who seems to have sent troops as well as money. However, Lothar's luck then turned. He argued with the Pope over Apulia, his soldiers mutinied, and he was forced to retreat despite impaling over 500 men in a desperate bid to restore discipline. Lothar died in the Alps on 4 December, depriving the Roman emperor of a powerful ally. In the aftermath the Normans were able to rally and retake their lands in southern Italy. 

None of this had any direct impact on John's campaign in distant Anatolia. While on the march east, he also made contact with Fatimid Egypt, perhaps to discuss trade or a more permanent alliance. This may imply that John intended his reconquest of eastern Anatolia to be permanent, with Egypt as a constant neighbour. To that end it made sense to establish friendly relations with the Fatimid Calpih.

John's enemy in the east was Leon I, ruler of Armenian Cilicia. In recent years Leon had waged war against the Frankish princes of the Holy Land, and defeated Raymond, Prince of Antioch. He then divided his forces, sending an army to attack the Roman stronghold of Seleukia, while Leon himself attended a meeting with Baldwin of Marash, a noble of the county of Edessa.

Unhappily for Leon, he had walked straight into a trap. He was treacherously seized and imprisoned in Antioch, after which his three sons fell to arguing. The eldest, Constantine, was blinded by his brothers, who were then also captured. 

These brutal power plays were all to John's advantage. The internal collapse of Cilicia made it vulnerable to conquest, and this was his chance to reclaim it for the Empire. He had every intention of seizing that opportunity.