first written records of Old Russian language appeared in the 10th century.
After the adoption of Christianity in 988, Old Church Slavonic was established
for the liturgical and literary purposes. It made a great influence on the
development of the Russian language, especially written one.
In the 17th century Russian got a lot of borrowings from the other European languages because policies of Peter the Great. At the beginning of the 19 century most of nobility spoke French and it added a lot of vocabulary to Russian.
In the 14th century Old Russian broke into Russian, Belarusian and Ukrainian.
Russian is spoken by about 146 million people on the territory of our country, it is also one of the official languages in Belarus , Kazakhstan , Crimea and some others.
Before the break of the Soviet Union Russian was the official language in all republics, now Russian speaking minorities there continue to use it at home.