The go 'Hokusai,' which is well known today, was an abbreviation of 'Hokusai Tokimasa,' which was named after the faith of Hokutatsu Myoken Bosatsu in the Nichiren sect, which deified the Polar star and the seven starts of the North Dipper.
現在広く知られる「北斎」は、当初名乗っていた「北斎辰政」の略称で、これは北極星および北斗七星を神格化した日蓮宗系の北辰妙見菩薩信仰にちなんでいる。