Beginning in the 4th century, the city was an important Christian centre, and was a seat of the Episcopate of Sirmium. Four Christian councils were held in Sirmium. At the end of the 4th century, Sirmium was brought under the sway of the Goths, and later, was again annexed to the Eastern Roman Empire. In 441, Sirmium was conquered by the Huns, and after this conquest, it remained for more than a century in the hands of various Germanic tribes, such were Eastern Goths and Gepids.