Indo-European languages

The Indo-European languages are a language family native to the northern Indian subcontinent, most of Europe, and the Iranian plateau, with additional native branches found in regions such as parts of Central Asia (e.g., Tajikistan and Afghanistan), southern Indian subcontinent (Sri Lanka and the Maldives) and Armenia. Historically, Indo-European languages were also spoken in Anatolia and Northwestern China. Some European languages of this family—English, French, Portuguese, Italian, Russian, Spanish, and Dutch—have expanded through colonialism in the modern period and are now spoken across several continents. The Indo-European family is divided into several branches or sub-families, including Albanian, Armenian, Balto-Slavic, Celtic, Germanic, Hellenic, Indo-Iranian, and Italic, all of which contain present-day living languages, as well as many more extinct branches.

Today the individual Indo-European languages with the most native speakers are English, Spanish, Portuguese, Russian, Hindustani, Bengali, Punjabi, French, and German; many others spoken by smaller groups are in danger of extinction. Over 3.4 billion people (42% of the global population) speak an Indo-European language as a first language—by far the most of any language family. There are about 446 living Indo-European languages, according to an estimate by Ethnologue, of which 313 belong to the Indo-Iranian branch.

All Indo-European languages are descended from a single prehistoric language, linguistically reconstructed as Proto-Indo-European, spoken sometime during the Neolithic or early Bronze Age (c. 3300 – c. 1200 BC). The geographical location where it was spoken, the Proto-Indo-European homeland, has been the object of many competing hypotheses; the academic consensus supports the Kurgan hypothesis, which posits the homeland to be the Pontic–Caspian steppe in what is now Ukraine and Southern Russia, associated with the Yamnaya culture and other related archaeological cultures during the 4th and early 3rd millennia BC. By the time the first written records appeared, Indo-European had already evolved into numerous languages, spoken across much of Europe, South Asia, and part of Western Asia. Written evidence of Indo-European appeared during the Bronze Age in the form of Mycenaean Greek and the Anatolian languages of Hittite and Luwian. The oldest records are isolated Hittite words and names, interspersed in texts that are otherwise in the unrelated Akkadian language (a Semitic language) found in texts of the Assyrian colony of Kültepe in eastern Anatolia dating to the 20th century BC. Although no older written records of the original Proto-Indo-European population remain, some aspects of their culture and their religion can be reconstructed from later evidence in the daughter cultures. The Indo-European family is significant to the field of historical linguistics as it possesses the second-longest recorded history of any known family after Egyptian and the Semitic languages, which belong to the Afroasiatic language family. The analysis of the family relationships between the Indo-European languages, and the reconstruction of their common source, was central to the development of the methodology of historical linguistics as an academic discipline in the 19th century.

The Indo-European language family is not considered by the current academic consensus in the field of linguistics to have any genetic relationships with other language families, although several disputed hypotheses propose such relations.

During the 16th century, European visitors to the Indian subcontinent began to notice similarities among Indo-Aryan, Iranian, and European languages. In 1583, English Jesuit missionary and Konkani scholar Thomas Stephens wrote a letter from Goa to his brother (not published until the 20th century) in which he noted similarities between North Indian languages and Greek and Latin.

Another account was made by Filippo Sassetti, a merchant born in Florence in 1540, who travelled to the Indian subcontinent. Writing in 1585, he noted some word similarities between Sanskrit and Italian (these included devaḥ/dio 'God', sarpaḥ/serpe 'serpent', sapta/sette 'seven', aṣṭa/otto 'eight', and nava/nove 'nine'). However, neither Stephens' nor Sassetti's observations led to further scholarly inquiry.

In 1647, Dutch linguist and scholar Marcus Zuerius van Boxhorn noted the similarity among certain Asian and European languages and theorized that they were derived from a primitive common language that he called Scythian. He included in his hypothesis Dutch, Albanian, Greek, Latin, Persian, and German, later adding Slavic, Celtic, and Baltic languages. However, Van Boxhorn's suggestions did not become widely known and did not stimulate further research.

Ottoman Turkish traveller Evliya Çelebi visited Vienna in 1665–1666 as part of a diplomatic mission and noted a few similarities between words in German and in Persian. Gaston Coeurdoux and others made observations of the same type. Coeurdoux made a thorough comparison of Sanskrit, Latin, and Greek conjugations in the late 1760s to suggest a relationship among them. Meanwhile, Mikhail Lomonosov compared different language groups, including Slavic, Baltic ("Kurlandic"), Iranian ("Medic"), Finnish, Chinese, "Hottentot" (Khoekhoe), and others, noting that related languages (including Latin, Greek, German, and Russian) must have separated in antiquity from common ancestors.