|Native speakers||90 million (3652)|
|Standard forms||Classical Selucian, Modern Standard Selucian|
|Official language in||Selucia, Pontesi,|
Aurorian Patriarchal Church, Religio Seluciana
|Recognised minority language in||Cildania, Barmenia|
The Selucian language (Lingua Seluciana) is part of the Superseleyan Family and placed in the Selucic tree. Over centuries the language became what it is now. During the unifying wars in the early history of Selucia nationalist leaders saw the need of one common language and it was a logical step to use the classical Selucian language which was used on all islands for business contracts or diplomatic treaties with each other. The literary language, called Modern Standard Selucian or Literary Selucian, is the only official form of Selucian. It is used in most written documents as well as in formal spoken occasions, such as lectures and news broadcasts. The standardized written Selucian is distinct from and more conservative than all of the spoken varieties, and the two exist in a state known as diglossia, used side-by-side for different societal functions. Colloquial Selucian dialects (Vulgar Selucian) continue to be spoken by Selucians in informal contexts, while in areas outside Selucia these dialects developed into the Selucic languages, such as Augustan, Canrillaise, Instalian, Ushalandan, or Arbanian.
Ancient Selucian was a pluricentric language, divided into many dialects. Each of the main islands of the archipelago had its own dialect, many of them with several subdivisions. Some dialects are found in standardized literary forms used in literature, while others are attested only in inscriptions. Of these the Aurorian dialect emerged as the most prestigious, due to the large and influential body of literature written in the language; when the Selucian League was established in 334 BCE, Aurorian Selucian became the most widely used Selucian dialect. Classical Selucian, the official language of the League, was based on the Aurorian dialect, and the language was also spoken in the Selucian colonies.
Classical Selucian continued to be used on the islands after Qedarite conquest, but began a slow and long decline, especially after the collapse of the Empire in 22 CE. Having lost its official status, Classical Selucian survived only as the liturgic language of the Hosian Church, while spoken varieties of the language began to diverge significantly from the Classical standard, eventually giving birth to modern Selucic languages in the former colonies.
During the Renascentia Classical literature was rediscovered, and with it widespread knowledge of Classical Selucian. Renascentia authors strived to immitate the writing of classical authors, creating a polished and artificial style that followed the prescriptions of 3rd century BCE Aurorian Selucian. The growing body of literature in Classical Selucian and the increasing divergence of colloquial dialects established the classical register as a common language throughout the islands, gaining acceptance as the language of diplomacy and trade in addition to its role as the language of literature and religion. This resulted in the perception of Classical Selucian as the national language of the Selucian nation, so that there was no major opposition to its establishment as sole official language following the Unification of Selucia. The nationalist movement was also instrumental in modernizing the language by adapting it to contemporary requirements, thus creating Modern Standard Selucian (abbreviated as MSS) as the contemporary literary standard of the language. Today Selucian can be said to exist in a state of diglossia, whereby MSS is the only language used for official and formal purposes, in spite of its lack of native speakers, while the colloquial dialects are used in day-to-day speech.
Due to the resurgence of Selucian during the Renascentia and to its role as the vehicle of Western Rite Hosianism, the language is widely used throughout Terra. Many national mottos are in this language, and before the rise of Luthori as the Terran global language, Selucian was used for international diplomacy, science, and trade. Additionally, the Selucian dialects outside the Selucian archipelago gave birth to modern Selucic languages, as these, unlike dialects used in Selucia, acquired official language status; although these languages may diverge from Classical Selucian as much as some Selucian dialects, linguists list them as separate languages.
There are two formal varieties of Selucian. One of these, known internationally as Modern Standard Selucian (MSS) and as sermo familiaris ("speech of the good families") in Selucia, is used in contexts such as writing, broadcasting, interviewing, and speechmaking. The other, Classical Selucian (sermo classicus, "classical speech"), is the language of Classical Antiquity, the Renascentia, and religion. It is rarely used except for religious purposes or quoting older classical texts. Modern Standard Selucian was deliberately developed in the late 18th century as a modernized version of Classical Selucian, and Selucian speakers do not typically make an explicit distinction between MSS and Classical Selucian. Today even the least educated citizens are exposed to MSS through public education and exposure to mass media, and so tend to use elements of it in speaking to others. A third and informal variety of Selucian is colloquial Selucian (sermo vulgaris, "vulgar speech"), which comprises the various unstandardized and informal dialects used in daily speech.