The Daily Question
In 1963, the Vatican issued a set of three stamps to honor the missionary Saints Cyril and Methodius, known as the Apostles to the Slavs. The L 70 value shows a map of the medieval state of Great Moravia, which is one of several places the two brothers were active. Most of Great Moravia’s territory is today part of :
1. the Czech and Slovak Republics
2. Hungary
3. Bulgaria and Serbia
4. Poland
Your answer was: the Czech and Slovak Republics
You are correct!!
Answer: Answer: The Czech and Slovak Republics, although it certainly included smaller parts of several neighboring countries. The brothers, who are considered the originators of the Cyrillic alphabet used today for writing several Slavic languages, are honored in Bulgaria as the national patrons of education. The Vatican has since issued additional stamps depicting the two saints.
See also:
Saints Cyrill And Methodius Vatican Notes Volume XII, Issue 6, May-June 1964, Page 7

Sts Cyril & Methodius
11th Century of the Evangelization of Greater Moravia
Scott # 369-371 (1964)