In Croatia, Popp families are Croats (from Vukovar ).
Prevalence
About 10 people with faimily name Popp live in Croatia today, in four households only. There were 10 of them in the middle of the past century, and their number remains constant. They are located in three Croatian cities only: in Zagreb (<5), Zadar (<5), and in Vukovar (<5).
Outside Croatia
Family name Popp is present in 65 countries worldwide. The family name "Popp " is used by some 20000 people in Germany , about 10000 in the United States , and some 2000 people in Romania.