Some Background: 

Shusaku Endo is a Japanese-Christian writer who frequently writes about Christian themes in his novels.  His greatest work, Silence, explores the conflict of faith faced by Catholic converts who were required to commit fumi, or the act of walking on a depiction of Christ’s face when the Emperor rejected the presence of Christianity in his kingdom.  In another book, Wonderful Fool, he includes a Christ-figure named Gaston Bonaparte (note connection to the nurse Gaston in this book).

Names:
Isobe = beach
Kiguchi = tree mouth
Tsukada = burial mound/rice paddy
Numada = rice paddy/swamp
Naruse (forming a ford); Mitsuko (beautiful harbor child)
Otsu = large harbor