Johannes Theodorus van Oyen was born in The Hague in 1893. Little is known about his education. Van Oyen went to work for Wolff Schoemaker in the former Dutch East Indies in 1919, first as a draughtsman and later as a partner and manager of the office in Semarang. Through Schoemaker, Van Oyen learns about the works of Frank Lloyd Wright. In 1924, Van Oyen continues by himself after the Firma 'C.P. Schoemakers and association, architects and engineers' is dissolved. In 1925, Van Oyen applies for membership in the BNA. In 1928, he establishes himself as an architect in Semarang and builds a residence there in the same year. He uses ceramics from the Porceleyne Fles for the tiling of the front gallery. From 1930 he calls himself an independent architect. In this capacity, Van Oyen designs various houses, stores, hotels, churches, monasteries and hospitals, mostly in a modern style. Among the projects he realized were the Grand-Hotel du Pavillon on Rijswijksestraat in Batavia (1939), a group of residential houses for the Construction Company Woningpark Buitenzorg in Buitenzorg (1939), a Roman Catholic church with accompanying friary house and school buildings on a site on Randoesarie in Semarang (1936, 1937) and the expansion of hotel and café-restaurant Hellendoorn in Surabaya (1937). J.Th. van Oyen died in 1944.