The Orthodox Church in Latvia from X to XX cnt.
The history of the Russian people is allied to the history of the Orthodox Church. The first records of the Orthodox religion in Latvia date back to the tenth century. The famous route ‘from the Varangians to the Greeks’ ran along the Daugava river (the Western Dvina). This was not only a trade route but a road that spread of Christianity. In the eastern regions of present day Latvia Christianity came from the neighbouring lands of Ancient Rus: from Polotsk, Pskov and Novgorod. Data from archaeological excavations as well as written sources bear witness to the presence of Orthodox Christianity on the territory of Latvia before the invasion of the crusaders. There are no historical facts to prove that the spread of the Orthodox faith was violent in character during those times.
The subjugation of the Latvian territories by the crusaders in the 13th century led to the imposition of Catholicism on the local population and the destruction of Orthodox churches.
For several centuries the only Orthodox temple in Riga was the Church of St. Nicolay the Miracle Worker in the Russian quarter of the town. This church was first mentioned in 1299. In the 17th century the church was destroyed. Only four icons have been preserved, now kept in the University of Uppsala (Sweden). In the east of Latvia some Orthodox churches have been preserved. It is a known fact that there was an Orthodox church in Ilūkste in 1582.
From the 18th century with the annexation of Latvia to the Russian Empire, the official Orthodox Church spread throughout the Latvian lands. In 1838 the Vicariate of Riga in the Diocese of Pskov was established. In 1847 the Orthodox School of Theology was established in Riga, and in 1851 the Ecclesiastical Academy started its work.
In 1850 the Vicariate of Riga was reformed into a separate Diocese of Riga. To start with the diocese included the provinces of Livonia and Courland. In 1865 its jurisdiction was extended to the province of Estonia.
By 1914 there were 267 churches within the Diocese of Riga, 71 houses of worship, 273,023 parishioners, and 457 Orthodox schools with 18,227 students.
Борис Инфаетьев. На пути к энциклопедии Латвийского Православия
Юрий Сидяков. Новая книга по истории Православия в Прибалтийском крае
Описание Мариенбургской церкви
Протоиерей Тарасий Фёдорович Серединский (Некролог). - Рига, 1897