The Armenian language (classical: ; reformed: "") occupies an independent branch of the Indo-European language tree. It is the official language of the Republic of Armenia and the Republic of Artsakh. It has historically been spoken throughout the Armenian Highlands and today is widely spoken in the Armenian diaspora. Armenian is written using the Armenian alphabet, introduced in 405 AD by Mesrop Mashtots. 

Armenian has developed since the separation from Indo-European mother tongue in the third millennium BCE to at least the time of the first Armenian dynasty (the Yervanduni dynasty, founded in the 6th century BCE). Hellenistic influences during the Artashesian Dynasty (2nd century BCE to 1st century CE) led to word borrowings from Greek and Latin. As the state language of the Arshakuni dynasty of Armenia (1st to 5th century CE) was Parthian, a large portion of Armenian vocabulary has been formed from Parthian borrowings. The earliest extant form of written Armenian is from the 5th century and is known as Classical Armenian (5th to 11th century); translations of the Bible and other religious texts during this period led to extensive word borrowings from Hebrew and Syriac. Middle Armenian (12th to 15th century) began with the establishment of the Armenian Kingdom of Cilicia in the 12th century and is marked by an increased influence of European languages on Armenian, particularly Old French (which had become the secondary language of the Cilician nobility) and Italian (which had become the secondary language of Cilician commerce). Middle Armenian is the first written form of Armenian to display Western-type voicing qualities. Early Modern Armenian (16th to 18th centuries) is a mix of Middle Armenian and an evolving, non-standardized literary Modern Armenian (in Constantinople, Venice, the Ararat plain, and the Persian Armenian communities, particularly New Julfa). As Armenian communities were spread across a large geographic area during this period, early Modern Armenian was influenced by the languages of host societies, with loan words being borrowed from Arabic, Turkish, Persian, Georgian, Latin, Greek, Italian, French, German, Polish, Hungarian, and Russian.
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Armenian has developed since the separation from Indo-European mother tongue in the third millennium BC