Guru Ram Das

At age 12, Bhai Jetha and his grandmother moved to Goindval, where they met Guru Amar Das, the third leader of Sikhism. The boy accepted the guru as his mentor, served him, and eventually joined his family by marrying his daughter. When it came time for Guru Amar Das to name his successor, he passed over his own sons and chose Bhai Jetha, citing his exemplary service, selfless devotion, and unquestioning obedience.
Renamed Ram Das ("slave of God"), Bhai Jetha became the fourth Guru of Sikhism in 1574. He faced hostility from the sons of Guru Amar Das, and shifted his official base to lands identified by Guru Amar Das as ''Guru-ka-Chak''. He founded the town of Ramdaspur, later renamed Amritsar and known as the holiest city of Sikhism. Unlike the first three Gurus, he appointed his own son as his successor, as would the fifth through tenth Sikh Gurus. He served until his death in 1581.
He is remembered in the Sikh tradition for expanding the ''manji'' organization for clerical appointments and donation collections to theologically and economically support the Sikh movement. Provided by Wikipedia
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