sentences:  This is believed to have largely been the result of concerns over the martial nature of the Japanese in the region (many were samurai serving as pirates and mercenaries), and over the shipments of weapons and munitions from Japan to Siam and southern Vietnam.In order to avoid potential violence within their chief port, the Trịnh Lords sought to avoid any significant permanent Japanese presence, though many notable and prominent Japanese merchants did frequently make port there.The Japanese established quite early a nihonmachi at Dilao, a suburb of Manila in the Spanish Philippines, where they numbered between 300 and 400 in 1593.