John of Rila was a Bulgarian hermit and the founder of the Rila Monastery, one of the most important spiritual centers in Bulgaria. He lived during the 10th century and is known for his ascetic lifestyle, dedicating his life to prayer and solitude in the Rila Mountains. His teachings and way of life attracted many followers, leading to the establishment of a monastic community. He was canonized as a saint by the Bulgarian Orthodox Church and is celebrated on July 18th each year. John of Rila is considered the patron saint of Bulgaria, symbolizing the country's spiritual heritage and devotion to Christianity.