Portuguese visitors and their South Asian and African crew members (or slaves) often engaged in slavery in Japan. More than hundreds of Japanese people, especially women, were sold as slaves. These mistaken assumptions were due to the Indian state of Goa being a central base for the Portuguese East India Company at the time, and due to a significant portion of the crew on Portuguese ships being Indian Christians. This began with the arrival of Portuguese ships to Japan in the 1540s, when the local Japanese people assumed that the Portuguese were from Tenjiku ( 天竺, 'Heavenly Abode'), the ancient Chinese name (and later Japanese name) for the Indian subcontinent, and thus assumed that Christianity was a new Indian religion. This practice later continued among visitors from 'the Western regions', mainly European traders who often came with their South Asian lascar crew (in addition to African crew members in some cases). From the 15th century, Chinese, Koreans, and other East Asian visitors frequented brothels in Japan.
