Zlački families are Croats and they are mostly from Zabok area. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Zabok area.
Prevalence
About 60 people with faimily name Zlački live in Croatia today, in 30 households. There were 70 of them in the middle of the past century, and their number decreased by 10 percent. They are only located in two Croatian cities and four other places, mostly in Zagreb (45), Radakovo in Zabok area (15), Sesvete (<5), Zapresic (<5), and in Popovaca in Kutina area (<5).
Outside Croatia
Family name Zlački (including: Zlacki , Zlacky ) is present in 7 countries on two continents. The family name "Zlacki " is used by small number of people in the United States and small number in Germany.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.