Svatopluk I of Moravia was a significant ruler of the Great Moravian Empire during the late 9th century. He reigned from around 870 to 894 and is known for unifying various Slavic tribes under his leadership. His reign marked a period of cultural and political development, as he sought to strengthen his territory against external threats. Svatopluk I is also recognized for his support of the Cyril and Methodius mission, which aimed to spread Christianity and literacy among the Slavic people. This mission led to the creation of the Glagolitic alphabet, facilitating the translation of religious texts into the Slavic language and promoting cultural identity.