The Oostkerk was designed by Bartholomeus Drijfhout and Pieter Post and was built between 1648 and 1667. After Drijfhout died in 1651, the building was continued under the Leiden architect Arent van 's Gravezande, who had just completed the Marekerk in Leiden. The white organ was built by Gebr. de Rijckere from Kortrijk in 1782. Two stained glass windows from 1664 still exist in the church, and the klokkenstoel contains a bell by C. Noorden and one by J.A. de Grave, 1715.
References:House of the Blackheads (Melngalvju nams) is a building situated in the old town of Riga. The original building was erected during the first third of the 14th century for the Brotherhood of Blackheads, a guild for unmarried German merchants in Riga. Major works were done in the years 1580 and 1886, adding most of the ornaments.
The structure was bombed to a ruin by the Germans June 28, 1941 and the remains demolished by the Soviets in 1948. The current reconstruction was erected from 1995 to 1999. Today the House of Blackheads serves as a museum and sometimes concert hall.