“European Courtiers” and “Father and Children” are a pair of Western-style paintings in the 17th-century Japan, like “Emperors and Kings on Horseback” or “Portrait of St. Francis Xavier” in the Kobe City Museum collection. Many of this kind of painting were supposed to be painted by Japanese painters in "Seminario", schools of the Society of Jesus in Nagasaki in the 17th century. However, Christianity was officially banned by the Tokugawa shogunate in 1614, and these Japanese painters had to secretly produce various artworks. Most of Western-style painting after 1614 were for the Christian worship, but there are some mysterious artworks depicts worldly European people, Chinese tales, or Japanese Buddhist monks in plain background. “European Courtiers” and “Father and Children” are presumed to be painted by the same painter as these curious paintings. Most of them have similar seals and signatures that are legible “Nobukata”, but unfortunately, there are few clue for this painter. “Portrait of Saint Nikkyo” (owned by the Seirenji temple in Hyogo pref.) is the only Nobukata’s painting that shows he might abandoned Christianity because Nikkyo was a monk of the Nichiren sect which was the most opposing religious group against Christians in Japan.