Ss. Cyril and Methodius, Greek brothers and priests, were born in 827 and 826. The emperor sent them to Russia in 861 to convert the Khazars to Christianity. They began to convert Moravians in 863 using their native language. The brothers developed a Slavonic language that eventually became what is currently known as Cyrillic. They received criticism for using native tongues instead of Greek or Latin in the liturgy, which was banned. However, the brothers’ use of native tongues helped Christianity take hold in Slavic countries. They are patron saints of ecumenism.