It was devised in 1986 by a research group at the Academy of Science of the USSR.
However, the majority of software at that period were made to be compatible with code page 437, as a result the Main code page has never gained any wide use.
With the introduction of the Russian version of MS-DOS in 1990 which by default uses code page 866, the Main code page has become obsolete.
Neither IBM nor Microsoft have ever supported this code page, so it has not been given its code page number by any vendor.
The Main code page was hardwired in some Soviet IBM PC clones such as ES PEVM or Iskra-1030 (however, other Soviet computers such as UKNC generally used KOI-7 or KOI-8).