Last name Ямагути (Soken 
, Yamaguchi , Hanroku , among others...) , around the world, is a common cognomen. The family name Ямагути is characteristic of British Virgin Islands, where it is quite a common surname, Japan, where it is quite a rare surname, and Bahamas. Measured by absolute frequency, the name is most common in Japan, Brazil, and the United States. Much less frequently, Ямагути is the forename as well as the last name.