Who were the two brothers sent to Moravia to help people?

The two brothers sent to Moravia to help people were Saints Cyril and Methodius. They were Byzantine missionaries in the 9th century who sought to spread Christianity among the Slavic peoples. They are also credited with creating the Glagolitic alphabet, which was the first alphabet used to transcribe Old Church Slavonic. Their efforts significantly contributed to the cultural and linguistic development of the Slavic nations.