The Swaminarayan Sampraday began as the Uddhav Sampraday and was led by Ramanand Swami. In 1799, Swaminarayan, then known as Neelkanth Varni, was initiated into the Uddhav Sampraday as an ascetic (Sadhu) by his guru, Ramanand Swami, and given the name "Sahajanand Swami". At the age of 21, Neelkanth Varni was given the leadership of the sect known as Uddhav Sampraday with the blessings of Ramanand Swami, who handed him control of the religious diocese shortly before his death. Fourteen days after Ramanand Swami died, Neelkanth Varni, now known as Sahajanand Swami, held a large gathering of followers at the town of Faneni. It was during this meeting that Swaminarayan introduced what he termed "the father of all Mantras", and then he was known as Swaminarayan. It should be noted that there was no swami who he had appointed his successor or as an ideal devotee at that time. The name refers wholly and solely to one entity, Swaminarayan. Thereafter the name "Swaminarayan Sampraday" came into existence Swaminarayan (3 April 1781 - 1 June 1830),also know as Sahajanand Swami, is the central figure in amodern sect of Hinduism known as the Swaminarayan Faith.Swaminarayan Hinduism,also known as the swaminarayan faith or the swaminarayan sect,is a modern tradition in the Vaishnava denomination of hinduism, in which followers offer devotion to and worship Swaminarayan as the Supreme manifestation of God.Since its origin, Swaminarayan Hinduism has been noted by its preservation of Gujarati cultural and linguistic traditions, devotion to the personality of Swaminarayan as supreme god, dedication to social service and a strict ethical code including uncompromising segregation of the genders.

 (taken from Vadtal mandir website)