As the Western Roman Empire began to fail Christianity began to spread beyond the borders of the former Empire. Christianity had spread from Roman Britain to Wales and Ireland and here a unique culture developed, which was in turn disseminated by Irish missionaries to Scotland and the continent. After pagan Anglo-Saxons invaded the former Roman colony of Britannia it took several hundred years for Christianity to re-root on English soil. The Gallo-Roman inhabitants of Gaul had been overrun by pagan Germanic tribes in France in the 5th century. The Frankish king Clovis I converted to Roman Catholicism in 496 and his newly established kingdom became a bastion of Christianity in the early Middle Ages. The doctrinal tensions between Rome and Constantinople led to a schism between western (Latin) and eastern (Greek) branches in 1054. The evangelization of Scandinavia began as early as the 9th century, though it was over 200 years before most of the Baltic region was Christianized. The Eastern Orthodox Church continued to send out missionaries to eastern Europe. In 988 Vladimir of Kiev was converted to Eastern Orthodoxy and he married the sister of the Byzantine Emperor, Basil II.