All of those terms (Bosnians, Bosniacs, Bosniaks) were used interchangeably, as common demonyms for the entire population of Bosnia, including all ethnic and religious groups.

[16] The earliest known record of the name Bosnia as a polity dates from the middle of the 10th century CE, in the Greek form Βόσονα, designating the region.

During that turbulent period, from the beginning of the 6th and up to middle of the 7th century, Early Slavs invaded the Byzantine Empire and settled throughout Southeastern Europe.

The remaining romanized population retreated -mainly to mountainous regions - while South Slavic tribes settled in plains and valleys, gradually coalescing into early principalities.

[19] During the twelfth century, local rulers developed the Banate of Bosnia, centered in the valley of the river Bosna.

During the 13th and 14th century, the Banate of Bosnia gradually expanded, incorporating regions of Soli, Usora, Donji Kraji and Zahumlje.

Many scholars classify these Bosnian Krstjani as Manichaean dualists related to the Bogomils of Bulgaria, while others question this theory, citing lack of historical evidence.

As a result of these divisions, no coherent religious identity developed in medieval Bosnia, in contrast to the situations in Croatia and Serbia.

First defeating the Serbs at the Battle of Kosovo and expanding westward, the Turks eventually conquered all of Bosnia and portions of neighboring Croatia.

Some historians contend that the Bosnian Krstjani converted en masse to Islam, seeking refuge from Catholic and Orthodox persecution.

Whatever the case, a native and distinct Muslim community developed among the Bosnians under Ottoman rule, quickly becoming dominant.

"[23][24] The policy tried to isolate Bosnia and Herzegovina from its irredentist neighbors (the Eastern Orthodox in Serbia, Catholics in Croatia, and the Muslims of the Ottoman Empire).

The empire tried to discourage the concept of Croat or Serb nationhood, which had spread to Bosnia and Herzegovina's Catholic and Orthodox communities from neighboring Croatia and Serbia in the mid-19th century.

[27][28] Consequently, Bosnian Muslims, or anyone who claimed a Bosnian/Bosniak ethnicity, were classified in Yugoslav population statistics as under the category 'regional affiliation.'

[28] In the 1961 census, the Bosniaks or Bosnian Muslims were categorized as an ethnic group defined as one of 'Muslim-Ethnic affiliation,' but not as a Yugoslav "constitutive nation" alongside Serbs and Croats.

"[33]According to Bringa, in Bosnia there is a singular, "trans-ethnic culture" that encompassed each ethnicity and makes different faiths, including Christianity and Islam, "synergistically interdependent".

[33] Still, large numbers of Bosnians are secular, a trend strengthened in the post-World War II in Bosnia and Herzegovina as they were part of the Communist political system that rejected traditional organized religion.According to the latest official population census made in Bosnia and Herzegovina, most of the population identified with Bosniak, Croat or Serb ethnicity.

In addition, a sizable population in Bosnia and Herzegovina believe that the term "Bosnians" defines a people who constitute a distinct collective cultural identity or ethnic group.