even further, into roughly twelve different principalities. The Crusades brought a shift in European trade routes that accelerated the decline of Kievan Rus'. In 1204, the forces of the Fourth Crusade sacked Constantinople, making the Dnieper trade route marginal. At the same time, the Livonian Brothers of the Sword (of the Northern Crusades) were conquering the Baltic region and threatening the Lands of Novgorod. Concurrently with it, the Ruthenian Federation of Kievan Rus' started to disintegrate into smaller principalities as the Rurik dynasty grew. The local Orthodox Christianity of Kievan Rus', while struggling to establish itself in the predominantly pagan state and losing its main base in Constantinople, was on the brink of extinction. Some of the main regional centres that developed later were Novgorod, Chernigov, Halych, Kiev, Ryazan, Vladimir-upon-Klyazma, Volodimer-Volyn and Polotsk. Novgorod Republic In the north, the Republic of Novgorod prospered because it controlled trade routes from the River Volga to the Baltic Sea. As Kievan Rus' declined, Novgorod became more independent. A local oligarchy ruled Novgorod; major government decisions were made by a town assembly, which also elected a prince as the city's military leader. In 1136, Novgorod revolted against Kiev, and became independent. Now an independent city republic, and referred to as "Lord Novgorod the Great" it would spread its "mercantile interest" to the west and the north; to the Baltic Sea and the low-populated forest regions, respectively. In 1169, Novgorod acquired its own archbishop, named Ilya, a sign of further increased importance and political independence. Novgorod enjoyed a wide degree of autonomy although being closely associated with the Kievan Rus. Novgorod avoided the Mongol invasion by agreeing to pay tribute to the Golden Horde, and was eventually conquered by Ivan III in 1478 . Northeast In the northeast, Slavs from the Kievan region colonized the territory that later would become the Grand Duchy of Moscow by subjugating and merging with the Finnic tribes already occupying the area. The city of Rostov, the oldest centre of the northeast, was supplanted first by Suzdal and then by the city of Vladimir, which become the capital of Vladimir-Suzdal. The combined principality of Vladimir-Suzdal asserted itself as a major power in Kievan Rus' in the late 12th century. In 1169, Prince Andrey Bogolyubskiy of Vladimir-Suzdal sacked the city of Kiev and took over the title of the grand prince to claim primacy in Rus'. Prince Andrey then installed his