Poster Cyrillic
The history of the Cyrillic alphabet began in 863 - it was a Greek alphabet with 17 additional letters. The Greek alphabet, on the other hand, has been in use since the late ninth or early eighth century BC.
The poster only shows the history of modern characters that are in official use in writing countries.
Montenegrin Cyrillic alphabet is not on the poster as since 2009 the official alphabet of Montenegro is Latin alphabet.