Scholars agree that Croatians began to add permanent surnames to their first names earlier than most other Slavic nations, particularly Serbs, Montenegrins and Macedonians.
This was due to several non-linguistic reasons, primarily social. As they were part of Roman Catholic tradition, antroponimic processes influenced by Vatican were similar as in other Central European nations, namely Italy, Austria, Germany & Hungary.
There are four key periods in the Croatian history that are important for the development of Croatian surnames:
First surnames among Croatian noblemen & aristocracy had been recorded in 12th century. However, the giving of permanent surnames at that time was very sporadic.
Aristocracy and other higher classes receive permanent surnames in 13th and 14th century, during the closure of the High Council in the cities of Dalmatia (region along the Eastern shore of the Adriatic Sea, predominantly inhabited by Croats). From that period, only lower classes didn’t have surnames.
The process of surnaming lower Croatian classes began in 16th century, after Catholic Church introduced the practice of keeping birth, marriage & death records followed by decisions of the Trident Council.
Having a surname in Croatia and countries within Austro-Hungarian Empire became obligatory after the introducion of the law known as Joseph patent in late 18th century.
(Source: Petar Šimunović, Razvitak imenske formule u Hrvata, Onomastica Jugoslavica 9, 1982, p. 283-292)
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