The Armenian language is the official language of Armenia and Nagorno-Karabakh Republic. It is spoken by 8 to 12 million people. It has historically been spoken throughout the Armenian Highlands and today is widely spoken in the Armenian diaspora.

Armenian has its own unique script, the Armenian alphabet, introduced in 405 AD by Mesrop Mashtots.

Armenia was a monolingual country by the 2nd century BC at the latest. Its language has a long literary history, with a 5th-century Bible translation as its oldest surviving text. Its vocabulary has been influenced by Western Middle Iranian languages, particularly Parthian, and to a lesser extent by Greek, Persian, and Arabic throughout its history. There are two standardized modern literary forms, Eastern Armenian and Western Armenian, with which most contemporary dialects are mutually intelligible.

Armenian has official status as a minority language in Cyprus, Poland and Romania. There are also Armenian speakers in many other countries, including Russia, Georgia, Lebanon, Iran, Syria, Turkey, Egypt and the USA.

Until the the early 1990s schools in Armenian taught in either Armenian or Russian, however after the collapse of the USSR, Armenian became the main medium of instruction and the Russian-medium schools were closed. In 2010 Russian language education was reintroduced in Armenia.

Sources:
Wikipedia
http://www.omniglot.com/writing/armenian.htm