Constantinople the same year, but effected nothing more than the customary devastation of the suburbs. The year 923 witnessed a solemn reconciliation between Rome and Constantinople; the Greeks were clever enough to prevent the Roman legates visiting Bulgaria on their return journey, and thereby administered a rebuff to Simeon, who was anxious to see them and enter into direct relations with Rome. In the same year Simeon tried to make an alliance with the Arabs, but the ambassadors of the latter were intercepted by the Greeks, who made it worth their while not to continue the journey to Bulgaria. In 924 Simeon determined on a supreme effort against Constantinople and as a preliminary he ravaged Macedonia and Thrace. When, however, he arrived before the city the walls and the catapults made him hesitate, and he entered into negotiations, which, as usual, petered out and brought him no adequate reward for all his hopes and preparations. In the west his arms were more successful, and he subjected most of the eastern part of Serbia to his rule. From all this it can be seen that he was no diplomat, though not lacking in enterprise and ambition. The fact was that while he made his kingdom too powerful for the Greeks to subdue (indeed they were compelled to pay him tribute), yet Constantinople with its impregnable walls, well-organized army, powerful fleet, and cunning and experienced statesmen, was too hard a nut for him to crack. Simeon extended the boundaries of his country considerably, and his dominion included most of the interior of the Balkan peninsula south of the Danube and east of the rivers Morava and Ibar in Serbia and of the Drin in Albania. The Byzantine Church greatly increased its influence in Bulgaria during his reign, and works of theology grew like mushrooms. This was the only kind of literature that was ever popular in Bulgaria, and although it is usual to throw contempt on the literary achievements of Constantinople, we should know but little of Bulgaria were it not for the Greek historians.