Origin in Tibet – Sera Je Drati Khangtsen was founded by “Je Jamchen Choeje Shakya Yeshe Pal Zangpo” in 1419 AD, long before Sera Thechenling or Sera Mahayana University was founded. It was also during the time of great Lama Tzongkhapa (1357 to 1419), who is the founder of Gelug School or the yellow hat (which is one of the four schools of Tibetan Buddhism).