Ganden was founded by Je Tsongkapa Lozang-dragpa(1357-1419). Je Tsongkhapa was prophesied by Buddha Shakyamuni. Buddha once said, After I have passed away from this world, when the earth becomes desolate, you (Lama Tsongphapa) will take the form of a child and enact the deeds of a Buddha.
One the the previous life of Lama Tsongkapa, as a small boy, he offering the Buddha a crystal rosary, Buddha then said that this small boy who has given me a crystal rosary will restore my teachings at a degenerate time in the future. The small boy was given in return a conch shell that had been presented to the Buddha by a naga king. Buddha entrusted this shell to his disciple, and the disciple was told to buried it in Tibet as an auspicious treasure for the future spread of the teachings.
Ganden Monastery comprises of two colleges, Jangtsey and Shartsey, which means, North Peak and East Peak respectively. According to one belief, they were named after their location to the Ganden's main temple.
On the 29th and 30th of each Tibetan month, the Jangtsey monks perform a full day rituals for their protector, while Shartsey performs the same rituals on the 28th and 29th. Each division also has its own assigned protector. On every 15th of Tibetan month, each individual division performs for a full day rituals of its protector.
As for the other two main Gelug monasteries in the Lhasa, their assigned protector of the Common Assembly of Drepung Monastery is Nechung, and Drepung Gomang's protector is Six-Armed Mahakala. The assigned protector of the Common Assembly of Sera and Sera Jey is Jamsing, Sera Jey is also has another protector known as Yangsang form of Hayagriva and Sera May's Assigned protector is Teu.
All three Ganden, Sera and Drepung Monastery, follows the early summer retreat from the 16th of the sixth Tibetan month to the 30th of the seventh month. During this retreat, a discourse is traditionally given based on Tsongkhapa's "Lamrim-chenmo" also known as the "Great Exposition on the Graded Stages of the Path".
The initial scope of the teachings are given by the junior of the Jangtsey and Sharjey Chojeys where the intermediate scope is taught by the senior of the two, the advanced scope will be taught by the Ganden Tripa.
Currently The monk population of Ganden was officially listed as 3,300, but back in 1959 it was 7,500. The monastery was totally torn down by the Chinese Communist. At present, the actual building is being partially reconstructed in Tibet. Where else In India, Ganden Monastery has been relocated in Mundgod, Karnataka State.