Family name Ямагата (Masakage 
, Yamagata 
, Ямагата 
) , in the world, is quite a rare cognomen. The cognomen Ямагата is characteristic of Cayman Islands, where it is quite a rare surname, Bermuda, and Slovenia. Measured by absolute frequency, it is the most numerous in the United States, Japan, and Brazil. Likewise, Ямагата is the forename as well as the last name.