Last name Breyn (Breyn 
, Брейн 
) , in all the world, is a very rare family name. The family name Breyn is habitual in Bulgaria, where it is a rare surname, Kyrgyzstan, where it is a very rare surname, and Germany. Measured by absolute frequency, the name is most common in Russia, Germany, and Bulgaria. Also, Breyn is the forename as well as the last name.