In Croatia, Mujaj families are Roms (from Rijeka ). In the past century, relatively most of Croatian residents bearing this family name were born in Rijeka.
Prevalence
About 10 people with faimily name Mujaj live in Croatia today, in three households only. They are located in one Croatian city only, in Rijeka (15).
Outside Croatia
Family name Mujaj (including: Muiai , Mujay and Mujei ) is present in 16 countries worldwide. The family name "Mujaj " is used by some 200 people in Albania , about 70 in Switzerland , and small number of people in the United States.