The Azerbaijani language is written in three scripts by Azerbaijaniphones: modified versions of Latin, Cyrillic and Arabic.

You can see some of the Latin version at this news portal: http://www.azerbaijan.az/portal/index_a.html?lang=az

What struck me was the use of the schwa in the Latin and Cyrillic versions. I don’t recall ever seeing the schwa used part of the standard alphabet for a language.  It is somewhat startling to see it used in upper case. Do any other languages use it?

Excerpt:

Aprelin 5-də Azərbaycanın birinci xanımı Mehriban Əliyeva Praqanın Dekorativ İncəsənət Muzeyində

I found this here:

These were selected to accommodate indigenous languages of Canada
which use the schwa. According to the sparse information I could
gather within the time frame to edit the CD ballot version, many
speakers of this languages tend to write using lower case only and do
not use upper case with a regularity accustomed to writers of (e.g.)
English. Thus, the use of upper case letters is not rigidly
standardized. When the schwa is uppercased, some use Ə, some use Ǝ,
some don’t care. Thus, in the context of Canadian indigenous
languages, Ə/Ǝ are glyph variants of the same letter called invariantly
“schwa” (the spelling “shwa” is also found often).

Thus, it was decided to supply the letter schwa at is full extent (as
it was to be included also to support Azerbaijani), and to include
the upper case Ǝ for those which prefer to use that glyph variant.
Having the lower case “latin small letter turned e” (which looks
exactly like the lower case schwa) on the same keyboard layout,
would appear as a confusing duplication for the ordinary user (who
is not a linguist or coding expert).

I have always wondered about the “latin small letter turned e”!

Thanks, languagehat.

The source of all wisdom reckons:

Azeri

When the new Latin alphabet was introduced for the Azerbaijani language on December 25, 1991, A-umlaut was selected to represent the sound /æ/. However, on May 16, 1992, it was replaced by the schwa letter, which also employs a capital form “Ə”. Although use of “Ä"/"ä" (also used in Tatar, Turkmen, and Gagauz) seems to be a simpler alternative as the schwa letter is absent in several character sets, particularly Turkish encoding, it was reintroduced; the schwa letter was used continuously from 1929 to 1991 to represent Azeri’s most-common vowel, in both post-Arabic alphabets (Latin and Cyrillic) of Azerbaijan.

EDIT: One thing that Wikipedia doesn’t tell me is when this upside down e was first used to represent the schwa sound. Anyone know?