Kalšan families are Croats and they are mostly from Prelog. In the past century, relatively most of Croatian residents bearing this family name were born in Prelog and Cakovec.
Prevalence
About 140 people with faimily name Kalšan live in Croatia today, in 60 households. There were 120 of them in the middle of the past century, and their number increased by 10 percent. They are located in 6 Croatian counties, in 6 cities and 10 other places, mostly in Otok (35), Prelog (30), Zagreb (25), Cakovec (15), and in Draskovec (<10).
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.