St. John was built on the site of the medieval court of the Bishop of Riga, Albert. In 1234, bishop Nicholaus sold the property to the Dominicans, who built a monastery in this place, and before 1297 they rebuilt the former chapel of the bishop’s court into a church (that year it was recorded for the first time in written sources). It was a Catholic temple until the Reformation, until 1523. Only in the fifteenth century, during the fights between the city and the Teutonic Order, it served as a storehouse of weapons transferred from the attacked castle. Perhaps it was damaged then, because at the end of the Middle Ages it underwent a thorough reconstruction. After 1523, the church belonged to a merchant who turned it into a stable. In 1582, after the capture of Riga by the Polish king Stefan Batory, the church was handed over to Protestants, at the same time its renovation and building of a new chancel was carried out. The church was seriously damaged during the great fire of Riga in 1677, then during the Napoleonic wars and for the last time during the Second World War.
The church was erected as a brick structure on a stone pedestal, single-nave, 12 meters wide and 19 meters high, built on an elongated quadrilateral plan, the central axis of which in the western part was directed to the south-west, showing a clear bent. The shape of the original presbytery is unknown, it can only be assumed that, following a pattern of mendicant monasteries, it was significantly elongated and most probably ended with a straight wall.
From the outside, the west facade was decorated with a gothic, stepped-pinnacle gable, referring to the Teutonic architecture from the Prussian region. The buttresses of the church were pulled inside, thanks to which the elevations remained smooth, separated only by large pointed-arched windows in the southern elevation, one for each of the four bays.
Inside, between massive buttresses, there were narrow chapels topped with stellar vaults, while those on the northern side were divided into two floors, and the upper ones received rib vaults. The space of the nave was topped at the turn of the 15th and 16th centuries with a magnificent net vault.
Alttoa K., Bergholde-Wolf A., Dirveiks I., Grosmane E., Herrmann C., Kadakas V., Ose J., Randla A., Mittelalterlichen Baukunst in Livland (Estland und Lettland). Die Architektur einer historischen Grenzregion im Nordosten Europas, Berlin 2017.