Linked from
The 30 pages that link to Old Church Slavonic, each with the reason it gives.
Cyrillic scriptRelated: Its manuscripts preserve early uses of Cyrillic.
Great MoraviaRelated: It gave the Moravian mission a language for worship and religious writing.
Glagolitic scriptRelated: Glagolitic was devised to write this language.
Clement of OhridRelated: Clement helped teach and extend the use of Slavic in Christian learning.
Cyrillic alphabetRelated: Its manuscripts preserve some of the earliest uses of Cyrillic.
Simeon I of BulgariaRelated: Simeon’s court supported its production and wider use.