East Slavic language
Ukrainian (, ) is one of the East Slavic languages in the Indo-European languages family, and it is spoken primarily in Ukraine. It is the first (native) language of a large majority of Ukrainians.
Written Ukrainian uses the Ukrainian alphabet, a variant of the Cyrillic script. The standard language is studied by the National Academy of Sciences of Ukraine and Potebnia Institute of Linguistics. Comparisons are often made between Ukrainian and Russian, another East Slavic language, yet there is more mutual intelligibility with Belarusian, and a closer lexical distance to West Slavic Polish and South Slavic Bulgarian.
Ukrainian is a descendant of Old East Slavic, a language spoken in the medieval state of Kievan Rus'. In the Grand Duchy of Lithuania, the language developed into Ruthenian, where it became an official language, before a process of Polonization began in the Polish–Lithuanian Commonwealth. By the 18th century, Ruthenian diverged into regional variants, and the modern Ukrainian language developed in the territory of present-day Ukraine. Russification saw the Ukrainian language banned as a subject from schools and as a language of instruction in the Russian Empire, and continued in various ways in the Soviet Union. Even so, the language continued to see use throughout the country, and remained particularly strong in Western Ukraine.
Linguistic development.
Theories.
Specific developments that led to a gradual change of the Old East Slavic vowel system into the system found in modern Ukrainian began approximately in the 12th/13th century (that is, still at the time of the Kievan Rus') with a lengthening and raising of the Old East Slavic mid vowels "e" and "o" when followed by a consonant and a weak yer vowel that would eventually disappear completely, for example Old East Slavic котъ /kɔtə/ ; Ukrainian кіт /kit/ 'cat' (via transitional stages such as /koˑtə̆/, /kuˑt(ə̆)/, /kyˑt/ or similar) or Old East Slavic печь /pʲɛtʃʲə/ ; Ukrainian піч /pitʃ/ 'oven' (via transitional stages such as /pʲeˑtʃʲə̆/, /pʲiˑtʃʲ/ or similar). This raising and other phonological developments of the time, such as the merger of the Old East Slavic vowel phonemes и /i/ and ы /ɨ/ into the specifically Ukrainian phoneme /ɪ ~ e/, spelled with и (in the 13th/14th centuries), and the fricativisation of the Old East Slavic consonant г /g/, probably first to /ɣ/ (in the 13th century), with /ɦ/ as a reflex in Modern Ukrainian, did not happen in Russian. Only the fricativisation of Old East Slavic г /g/ occurred in Belarusian, where the present-day reflex is /ɣ/.
Ahatanhel Krymsky and Aleksey Shakhmatov assumed the existence of the common spoken language of Eastern Slavs only in prehistoric times. According to their point of view, the diversification of the Old East Slavic language took place in the 8th or early 9th century.
Russian linguist Andrey Zaliznyak stated that the Old Novgorod dialect differed significantly from that of other dialects of Kievan Rus' during the 11th–12th century, but started becoming more similar to them around the 13th–15th centuries. The modern Russian language hence developed from the fusion of this Novgorod dialect and the common dialect spoken by the other Kievan Rus', whereas the modern Ukrainian and Belarusian languages developed from dialects which did not differ from each other in a significant way.
Ukrainian linguist Stepan Smal-Stotsky denies the existence of a common Old East Slavic language at any time in the past. Similar points of view were shared by Yevhen Tymchenko, Vsevolod Hantsov, Olena Kurylo, Ivan Ohienko and others. According to this theory, the dialects of East Slavic tribes evolved gradually from the common Proto-Slavic language without any intermediate stages during the 6th through 9th centuries. The Ukrainian language was formed by convergence of tribal dialects, mostly due to an intensive migration of the population within the territory of today's Ukraine in later historical periods. This point of view was also supported by George Shevelov's phonological studies, which argue that specific features were already recognizable in the southern dialects of Old East Slavic (seen as ancestors to Ukrainian) as far back as these varieties can be documented.
Origins and developments during medieval times.
As a result of close Slavic contacts with the remnants of the Scythian and Sarmatian population north of the Black Sea, lasting into the early Middle Ages, the appearance of the voiced fricative γ/г (romanized "h"), in modern Ukrainian and some southern Russian dialects is explained by the assumption that it initially emerged in Scythian and related eastern Iranian dialects, from earlier common Proto-Indo-European "*g" and "*gʰ".
During the 13th century, when German settlers were invited to Ukraine by the princes of the Kingdom of Ruthenia, German words began to appear in the language spoken in Ukraine. Their influence would continue under Poland not only through German colonists but also through the Yiddish-speaking Jews. Often such words involve trade or handicrafts. Examples of words of German or Yiddish origin spoken in Ukraine include ("roof"), ("pipe"), ("market"), ("furrier"), and ("master" or "craftsman").
Developments under Poland and Lithuania.
In the 13th century, eastern parts of Rus (including Moscow) came under Tatar rule until their unification under the Tsardom of Muscovy, whereas the south-western areas (including Kyiv) were incorporated into the Grand Duchy of Lithuania. For the following four centuries, the languages of the two regions evolved in relative isolation from each other. Direct written evidence of the existence of the Ukrainian language dates to the late 16th century. By the 16th century, a peculiar official language formed: a mixture of the liturgical standardised language of Old Church Slavonic, Ruthenian and Polish. The influence of the latter gradually increased relative to the former two, as the nobility and rural large-landowning class, known as the szlachta, was largely Polish-speaking. Documents soon took on many Polish characteristics superimposed on Ruthenian phonetics.
Polish–Lithuanian rule and education also involved significant exposure to the Latin language. Much of the influence of Poland on the development of the Ukrainian language has been attributed to this period and is reflected in multiple words and constructions used in everyday Ukrainian speech that were taken from Polish or Latin. Examples of Polish words adopted from this period include "zavzhdy" (always; taken from old Polish word "zawżdy") and "obitsiaty" (to promise; taken from Polish "obiecać") and from Latin (via Polish) "raptom" (suddenly) and "meta" (aim or goal).
Significant contact with Tatars and Turks resulted in many Turkic words, particularly those involving military matters and steppe industry, being adopted into the Ukrainian language. Examples include "torba" (bag) and "tyutyun" (tobacco).
Because of the substantial number of loanwords from Polish, German, Czech and Latin, early modern vernacular Ukrainian ("prosta mova", "simple speech") had more lexical similarity with West Slavic languages than with Russian or Church Slavonic. By the mid-17th century, the linguistic divergence between the Ukrainian and Russian languages had become so significant that there was a need for translators during negotiations for the Treaty of Pereyaslav, between Bohdan Khmelnytsky, head of the Zaporozhian Host, and the Russian state.
By the 18th century, Ruthenian had diverged into regional variants, developing into the modern Belarusian, Rusyn, and Ukrainian languages.
Chronology.
The accepted chronology of Ukrainian divides the language into Old Ukrainian, Middle Ukrainian, and Modern Ukrainian. Shevelov explains that much of this is based on the character of contemporary written sources, ultimately reflecting socio-historical developments, and he further subdivides the Middle period into three phases:
Ukraine annually marks the Day of Ukrainian Writing and Language on 9 November, the Eastern Orthodox feast day of Nestor the Chronicler.
History of the spoken language.
Rus' and Kingdom of Ruthenia.
The era of Kievan Rus' (c. 880–1240) is the subject of some linguistic controversy, as the language of much of the literature was purely or heavily Old Church Slavonic. Some theorists see an early Ukrainian stage in language development here, calling it Old Ruthenian; others term this era Old East Slavic. Russian theorists tend to amalgamate Rus' to the modern nation of Russia, and call this linguistic era Old Russian. However, according to Russian linguist Andrey Zaliznyak (2012), people from the Novgorod Republic did not call themselves "Rus'" until the 14th century; earlier Novgorodians reserved the term "Rus'" for the Kiev, Pereyaslavl and Chernigov principalities. At the same time as evidenced by contemporary chronicles, the ruling princes and kings of Galicia–Volhynia and Kiev called themselves "people of Rus'" (in foreign sources called "Ruthenians"), and Galicia–Volhynia has alternately been called the Principality or Kingdom of Ruthenia.
Also according to Andrey Zaliznyak, the Novgorodian dialect differed significantly from that of other dialects of Kievan Rus during the 11th–12th century, but 
started becoming more similar to them around 13th–15th centuries. The modern Russian language hence developed from the fusion of this Novgorodian dialect and the common dialect spoken by the other Kievan Rus, whereas the modern Ukrainian and Belarusian languages developed from the dialects which did not differ from each other in a significant way.
Under Lithuania/Poland and Muscovy/Russia.
After the fall of the Kingdom of Ruthenia, Ukrainians mainly fell under the rule of Lithuania and then Poland. Local autonomy of both rule and language was a marked feature of Lithuanian rule. In the Grand Duchy of Lithuania, Old East Slavic became the language of the chancellery and gradually evolved into the Ruthenian language. Polish rule, which came later, was accompanied by a more assimilationist policy. By the 1569 Union of Lublin that formed the Polish–Lithuanian Commonwealth, a significant part of Ukrainian territory was moved from Lithuanian rule to Polish administration, resulting in cultural Polonization and visible attempts to colonize Ukraine by the Polish nobility.
Many Ukrainian nobles learned the Polish language and converted to Catholicism during that period in order to maintain their lofty aristocratic position. Lower classes were less affected because literacy was common only in the upper class and clergy. The latter were also under significant Polish pressure after the Union with the Catholic Church. Most of the educational system was gradually Polonized. In Ruthenia, the language of administrative documents gradually shifted towards Polish.
Polish has had heavy influences on Ukrainian (particularly in Western Ukraine). The southwestern Ukrainian dialects are transitional to Polish. As the Ukrainian language developed further, some borrowings from Tatar and Turkish occurred. Ukrainian culture and language flourished in the sixteenth and first half of the 17th century, when Ukraine was part of the Polish–Lithuanian Commonwealth, albeit in spite of being part of the PLC, not as a result. Among many schools established in that time, the Kyiv-Mohyla Collegium (the predecessor of the modern Kyiv-Mohyla Academy), founded by the Orthodox Metropolitan Peter Mogila, was the most important. At that time languages were associated more with religions: Catholics spoke Polish, and members of the Orthodox church spoke Ruthenian.
The 1654 Pereiaslav Agreement between Cossack Hetmanate and Alexis of Russia divided Ukraine between the Polish–Lithuanian Commonwealth and the Tsardom of Russia. During the following century, both monarchies became increasingly intolerant of Ukrainian own cultural and political aspirations. Ukrainians found themselves in a colonial situation. The Russian centre adopted the name "Little Russia" for Ukraine and "Little Russian" for the language, an expression that originated in Byzantine Greek and may originally have meant "old, original, fundamental Russia", and had been in use since the 14th century. Ukrainian high culture went into a long period of steady decline. The Kyiv-Mohyla Academy was taken over by the Russian Empire. Most of the remaining Ukrainian schools also switched to Polish or Russian in the territories controlled by these respective countries, which was followed by a new wave of Polonization and Russification of the native nobility. Gradually the official language of Ukrainian provinces under Poland was changed to Polish, while the upper classes in the Russian part of Ukraine used Russian.
In Austrian Galicia and Lodomeria (1772–1918).
After the 1772 First Partition of Poland, when the lands annexed by the Austrian Habsburg monarchy were reorganised as the Kingdom of Galicia and Lodomeria, the Habsburg administration was initially surprised to find out that, apart from Poles, there were a lot of other people living in it whom they began calling "Ruthenen" ("Ruthenians" or "Rusyny"). They differed from the Poles in that the vast majority of them adhered to the Greek Catholic faith (organised as the Ruthenian Uniate Church) rather than Roman Catholic, and that their liturgical language was Church Slavonic rather than Latin. Most of them had not received much education; they used Ruthenian only as a spoken language, few could read or write, and those who did more often used Polish or (increasingly) German instead. As Empress Maria Theresa had introduced