In Croatia, Ritza families are Croats by relative majority, equally Hungarians (from Zagreb ).
Prevalence
Only a few people with faimily name Ritza live in Croatia today, in two households only. There were 0 of them in the middle of the past century, and their number remains constant. They are located in one Croatian city only, in Zagreb (<5).
Outside Croatia
Family name Ritza is present in 8 countries worldwide. The family name "Ritza " is used by some 80 people in Indonesia , about 80 in Canada , and small number of people in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1926 in source Emigration Commission Zagreb.