Complex sentence: Significant attempts to curtail the influence of Christian missionaries in Japan date to 1587 during the shogunate of Toyotomi Hideyoshi, but in 1614 Ieyasu was significantly concerned about Spanish territorial ambitions that he signed a Christian Expulsion Edict.
Split into simpler sentences: Significant attempts to curtail the influence of Christian missionaries in Japan date to 1587 during the shogunate of Toyotomi Hideyoshi. However in 1614, Ieyasu was sufficiently concerned about Spanish territorial ambitions that he signed a Christian Expulsion Edict.