Bulgarian is a Southern Slavic language with about 12 million speakers mainly in Bulgaria, but also in Ukraine, Macedonia, Serbia, Turkey, Greece, Romania, Canada, USA, Australia, Germany and Spain. Bulgarian was the first Slavic language to be written: it start to appear in writing during the 9th century in the Glagolitic alphabet, which was gradually replaced by an early version of the Cyrillic alphabet over the following centuries.
In AD 886, the Bulgarian Empire introduced the Glagolitic alphabet, devised by Saint Cyril and Methodius in the 850s. The Glagolitic alphabet was gradually superseded in later centuries by the Cyrillic script, developed around the beginning of the 10th century.
The two brothers, Sts. Cyril and Methodius (or Constantine and Methodius) – known as the Apostles of the Slavs, were born in Thessalonica, in 827 and 826 respectively. Though belonging to a senatorial family, they renounced secular honours and became priests. They were living in a monastery on the Bosphorus, when the Khazars sent to Constantinople for a Christian teacher. Cyril was selected and was accompanied by his brother. They learned the Khazar language and converted many of the people. Soon after their Khazar mission, came the invitation of the Moravian Prince Rostislav, who sought missionaries able to preach in the Slavonic vernacular (people’s) language, and thereby check German influence in Moravia - the Moravians wished a teacher who could instruct them and conduct Divine service in the Slavonic tongue. On account of their acquaintance with that language, Cyril and Methodius were chosen for their work. In preparation for it Cyril invented a new alphabet and, with the help of Methodius, translated the Gospels and the necessary liturgical books into that new South Slavonic language. They went to Moravia in 863, and laboured over the translations for four and a half years.
The Old Bulgarian language was the basis of Russian, Serbian, Slovenian, and Croatian variants and gained the significance of a universal literary Slavonic language. The modern Bulgarian literary language is characterized by dropping off the case forms, by the use of the definite article, by nine tenses, four moods, etc.