Which country adopted the Cyrillic alphabet first?

Answer 1

The layout of the alphabet is derived from the early Cyrillic alphabet, itself a derivative of the Glagolitic alphabet, a ninth century uncial cursive usually credited to two bulgarian monk brothers from Thessaloniki (Byzantine), Saint Cyril and Saint Methodius.
Although it is widely accepted that the Glagolitic alphabet was invented by Saints Cyril and Methodius, the origins of the early Cyrillic alphabet are still a source of much controversy. Though it is usually attributed to Saint Clement of Ohrid, disciple of Saint Cyril and Saint Methodius from Bulgarian Macedonia, the alphabet is more likely to have developed at the Preslav Literary School in northeastern Bulgaria, where the oldest Cyrillic inscriptions have been found, dating back to the 940s. The theory is supported by the fact that the Cyrillic alphabet almost completely replaced the Glagolitic in northeastern Bulgaria as early as the end of the tenth century, whereas the Ohrid Literary School—where Saint Clement worked—continued to use the Glagolitic until the twelfth century. Of course, as the disciples of St. Cyril and Methodius spread throughout the First Bulgarian Empire, it is likely that these two main scholarly centres were a part of a single tradition.

Answer 2

Officially, the answer is Bulgaria and this is the answer I think your looking for.

However, from a historian's point of view, there is no simple answer to your question.

The basic Cyrillic alphabet form already existed in the Byzantine Empire having evolved from the capital letters of the Greek alphabet. It was the alphabet that the Byzantine Greeks used on all their monuments and grave sites in both Greece and Asia Minor (Turkey).

Some historians believe that the Cyril and Methodius story is somewhat of a myth and that the alphabet spread more by way of trade and commerce between Slavs and Byzantines rather than by religious evangelism. Thus, it may actually have entered southern Russia (Ukraine) and Bulgaria at about the same time.

Answer 3

Βulgaria (not as it is today).
http://www.bnr.bg/RadioBulgaria/Emission_English/News/CyrilEU.htm
(To the first answerer:) They were NOT Bulgarian, they were Byzantine. There is a DIFFERENCE. And Thessaloniki at that time was part of the Byzantine Empire - Byzantine Greek Language had replaced Latin in the vast majority of the cases.
Since you copy from somewhere, copy as you find.
I am giving the link:
http://en.wikipedia.org/wiki/Cyrillic#History

Answer 4

that would be Bulgaria, where the alphabet was first developed.

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