KNIAZ Boris I Street in the centre of Sofia was named after the famous Bulgarian ruler who made Christianity the official religion in his kingdom.

Boris I, who occupied the Bulgarian throne from 852 to 889, started his rule in a time when the Bulgarian society was still divided into Slavs and Proto-Bulgarians. The two groups had completely different religious beliefs and that was a serious obstacle to consolidation of the state. In addition to the political centralisation of power, Bulgaria desperately needed cultural and religious consolidation too.

In 863, Boris I announced his decision to convert to Christianity - himself and the whole state.

The Catholic church in Rome and the Eastern Orthodox Church in Constantinople started competing for religious influence in Bulgaria.

Both tried to convince the Bulgarian ruler to convert to their type of Christianity. Byzantium, however, employed military actions to that end. It staged a fake attack on the Bulgarian lands and demanded that to baptise the Bulgarian delegation that was sent to Constantinople for peace negotiations.

Boris I had no choice but to agree. Besides, he himself preferred the principles of Orthodox Christianity. With the baptising of the Bulgarian delegations the so-called `deep peace' was achieved which guaranteed that there would be no attacks from Byzantium for 30 years.

In 864, Boris I together with his entire court and many other Bulgarians accepted Christianity and changed his pagan title khan to kniaz (prince). He also accepted the name of his godfather, Byzantine emperor Michael III and was named Kniaz Boris-Michael.

The act of baptising the Bulgarians proved a catalyst to the process of assimilation of the Proto-Bulgarians by the Slavic majority. As a result of this process the Bulgarian nationality - Slavic in its self-identification, language and traditions - crystallised.

In 886, Kniaz Boris-Michael invited the disciples of the Slav apostles Cyril and Methodius, who created the Slav alphabet to Bulgaria.

They were received with great honours. With the approval of Boris I, two spiritual centres of tremendous significance for Slavic culture were formed: in the capital city Pliska, as well as in the other central town of the Bulgarian kingdom - Ohrid (in Macedonia today). In Ohrid alone, over the course of seven years, nearly 3,500 students were educated in the principles of the new alphabet.

In 893, Boris I summoned a Church Council in Pliska. At the meeting a decision was taken to change the capital of Bulgaria. The pagan capital Pliska was replaced by Veliki Preslav (today Preslav, a town in north-eastern Bulgaria).

The Byzantine priests were sent away, because the country already had well-educated clergymen of its own. And most importantly, at the 893 Council the Bulgarian Slavic language was declared to be the official administrative and church language. The language was comprehensible to the common people. It formed the basis of the Bulgarian cultural tradition.

Having accomplished his life's work, Boris I retired to a monastery. His rule had a cultural impact on the development of all Slavs and the whole of Eastern Europe. He died in 907. However, before finding eternal peace, in 893 he had to prove his unconditional loyalty to Christianity once again; in 893 he left the monastery for a while - to dethrone and blind his first-born son Prince Vladimir, who had been conspiring to restore paganism.

After his death, Boris I became the first saint of the Bulgarian Church.