"Over the course of the 1630s, Iemitsu issued a series of edicts restricting Japan's intercourse with the outside world. Japanese, who had since the 1590s traveled extensively in East and Southeast Asia (and, in rare instances, much farther afield), were now forbidden from leaving the country, or returning, under pain of death. Europeans were expelled from the country, with the exception of those associated with the Dutch East India Company, who were restricted to the manmade island of Dejima, in Nagasaki harbor." (Wikipedia, because why not)

I think it was during Iemitsu's reign (Hidetada's eldest son; Hidetada(2nd ruler) was Ieyasu's(1st ruler) descendant) that Japan was closed to the outside world. Pretty much, Kuro returned after the reign of Ieyasu and Hidetada.

But that's just history :D Thanks for the acceptance!