Patriarch John Kamateros died in June 1206. The Orthodox clergy of Constantinople asked Pope InnocentIII to authorize them to elect a new patriarch, but the Latin authorities opposed their plan. The new Latin Emperor of Constantinople, Henry of Flanders, made an alliance with David Komnenos against Theodore. Theodore decided to capture Heraclea Pontica from David, but the Latins attacked his army from the rear when he was marching towards the town, and he had to abandon the campaign to chase the Latin troops off. The Latins invaded Asia Minor and captured Nicomedia and Cyzicus during the winter of 1206–1207. Theodore in turn allied himself with Kaloyan, who launched an incursion into Thrace, forcing Emperor Henry to recall his troops from Asia Minor. After Theodore and his brothers had laid siege to Nicomedia, Henry agreed to sign a two-year truce, authorizing Theodore to destroy two fortifications at Nicomedia and Cyzicus.