[7] Isabelle T. Keindler writes:Gradually major differences developed in customs, language and even physical appearance (until their conversion to Christianity the Erzia and Moksha did not intermarry and even today intermarriage is rare.)

When a speaker wishes to refer to Mordvinians as a whole, he must use the term "Erzia and Moksha"[8]The ethnonym Mordva is possibly attested in Jordanes' Getica in the form of Mordens who, he claims, were among the subjects of the Gothic king Ermanaric.

[9] A land called Mordia at a distance of ten days journey from the Petchenegs is mentioned in Constantine VII's De administrando imperio.

After the Mongol invasion of Rus', the name Mordvin rarely gets mentioned in Russian annals, and is only quoted after the Primary Chronicle up until the 15th–17th centuries.

[13][anachronism] The first written mention of Erzya is considered to be in a letter dated to 968 AD, by Joseph, the Khazar khagan, in the form of arisa.

[citation needed] Researchers have distinguished the ancestors of the Erzya and the Moksha from the mid-1st century AD by the different orientations of their burials and by elements of their costumes and by the variety of bronze jewellery found by archaeologists in their ancient cemeteries.

All these conventions accepted similar resolutions with appeals to democratize political and public life in their respective republics and to support the national revival of Finno-Ugric peoples.

Estonia had a strong influence on moods and opinions that dominated these conventions, (especially among national-oriented intellectuals) because many students at the University of Tartu were from Finno-Ugric republics of Russia.

Erzya is spoken in the northern and eastern and north-western parts of Mordovia, as well as in the adjacent oblasts of Nizhny Novgorod, Penza, Samara, Saratov, Orenburg, and Ulyanovsk, and in the republics of Chuvashia, Tatarstan, and Bashkortostan.

Due to differences in phonology, lexicon, and grammar, Erzya and Moksha are not mutually intelligible, to the extent that the Russian language is often used for intergroup communications.

2010s most Finnic linguists considered Mordvinic and Mari languages as a single subdivision of the so-called Volga-Finnic branch of the Uralic family.

[citation needed] The Mordvins are divided into two ethnic subgroups[26][27][obsolete source] and three further subgroups:[4][28][obsolete source] Mokshin concludes that the above grouping does not represent subdivisions of equal ethnotaxonomic order, and discounts Shoksha, Karatai and Teryukhan as ethnonyms, identifying two Mordvin sub-ethnicities, the Erzya and the Moksha, and two "ethnographic groups", the Shoksha and the Karatai.

[29][obsolete source] Two further formerly Mordvinic groups have assimilated to (Slavic and Turkic) superstrate influence: Latham (1854) quoted a total population of 480,000.

According to estimates by Tartu University made in the late 1970s,[citation needed] less than one third of Mordvins lived in the autonomous republic of Mordovia, in the basin of the Volga River.

The worship of trees, water (especially of the water-divinity which favours marriage), the sun or Shkay, who is the chief divinity, the moon, the thunder and the frost, and of the home-divinity Kardaz-scrko[dubious – discuss] still exists among them; and a small stone altar or flat stone covering a small pit to receive the blood of slaughtered animals can be found in many houses.

On the fortieth day after the death of a kinsman the dead [one] is not only supposed to return home, but a member of his household represents him, and, coming from the grave, speaks in his name...

They have a considerable literature of popular songs and legends, some of them recounting the doings of a king Tushtyan who lived in the time of Ivan the Terrible[obsolete source].

Convention forms Aťań Eźem, that is operative between Promks sessions and elects Inyazor, who presents Erzya people and speaks on behalf of all the nation.

In the event that there are any legal limitations for creation and operation of national parties (such prohibition exists in Russian Federation nowadays), then plenary powers of Promks are carried by Aťań Eźem.

[38] The 1911 Encyclopædia Britannica[34] noted that the Mordvins, although they had largely abandoned their language, had "maintained a good deal of their old national dress, especially the women, whose profusely embroidered skirts, original hair-dress large ear-rings which sometimes are merely hare-tails, and numerous necklaces covering all the chest and consisting of all possible ornaments, easily distinguish them from Russian women."

[4] James Bryce described "the peculiar Finnish physiognomy" of the Mordvin diaspora in Armenia, "transplanted hither from the Middle Volga at their own wish", as characterised by "broad and smooth faces, long eyes, a rather flattish nose".