Croatian language (hrvatski jezik) is a South Slavic language which is used primarily by the inhabitants of Croatia and Croats in Bosnia and Herzegovina and parts of the Croatian diaspora. It is one of the standard versions of the Central-South Slavic diasystem.
Croatian is based on the Ijekavian pronunciation of Štokavian dialect (with some influence from Čakavian and Kajkavian) and written with the Croatian alphabet.
The modern Croatian standard language is a continuous outgrowth of more than nine hundred years of literature written in a mixture of Croatian Church Slavonic and the vernacular language. If the subject is narrowed out, Croatian Church Slavonic had been abandoned by the mid-1400s, and Croatian "purely" vernacular literature has existed for more than five centuries.
The beginning of the Croatian written language can be traced to the 9th century, when Old Church Slavonic was adopted as the language of the liturgy. This language was gradually adapted to non-liturgical purposes and became known as the Croatian version of Old Slavonic. The two variants of the language, liturgical and non-liturgical, continued to be a part of the Glagolitic service as late as the mid-9th century.
Until the end of the 11th century, Croatian medieval texts were written in three scripts: Latin, Glagolitic, and Croatian Cyrillic (arvatica, poljičica, bosančica), and also in three languages: Croatian, Latin and Old Slavic. The latter developed into what is referred to as the Croatian variant of Church Slavonic between the 12th and 16th centuries.
The most important early monument of Croatian literacy is the Baška tablet from the late 11th century. It is a large stone tablet found in the small church of St. Lucy on the Croatian island of Krk, containing text written mostly in čakavian, today a dialect of Croatian, and in Croatian Glagolitic script. It is also important in the history of the nation as it mentions Zvonimir, the king of Croatia at the time. However, the luxurious and ornate representative texts of Croatian Church Slavonic belong to the later era, when they coexisted with the Croatian vernacular literature. The most notable are the "Missal of Duke Novak" from the Lika region in northwestern Croatia (1368), "Evangel from Reims" (1395, named after the town of its final destination), "Missal of Duke Hrvoje" from Bosnia and Split in Dalmatia (1404) and the first printed book in Croatian language (1483).
Also, during the 13th century Croatian vernacular texts began to appear, the most important among them being "Istrian land survey", 1275 and "The Vinodol Codex", 1288., both in the Čakavian dialect.
The Štokavian dialect literature, based almost exclusively on Čakavian original texts of religious provenance (missals, breviaries, prayer books) appeared almost a century later. The most important purely Štokavian vernacular text is Vatican Croatian Prayer Book (ca. 1400).
Both the language used in legal texts and that used in Glagolitic literature gradually came under the influence of the vernacular, which considerably affected its phonological, morphological and lexical systems. From the 14th and the 15th centuries, both secular and religious songs at church festivals were composed in the vernacular.
Writers of early Croatian religious poetry (začinjavci), translators and editors gradually introduced the vernacular into their works. These začinjavci were the forerunners of the rich literary production of the 15th and 16th centuries. The language of religious poems, translations, miracle and morality plays contributed to the popular character of medieval Croatian literature.