Although he was enthroned as the 18th Abbot of Ralung (rwa lung), the seat of the hereditary lineage and first 'brug pa monastery to be established in Tibet, Ngawang Namgyal was compelled to flee Tibet in 1616 in order to escape the persecution of the powerful king of Tsang, a supporter of the Karma Kagyu, who recognized Pagsam Wangpo (dpag bsam dbang po) (1592-1641) [his own nephew and an illegitimate son of the 'phyongs rgyas myriarch], as the 5th Drukchen incarnation.
Following a prophecy of Padmasambhava in the gsang ba'i nor bu’i thig le’i rgyud (lho rong lho sgo bas mthar bsti gnas tshol // de ltar byas na bod yul mi lo bdun // bsgom bsgrub byas las gnas der zhag bdun sgrub thag nye //) and a prophecy of Pema Karpo, Ngawang Namgyal left for western Bhutan, where the Drukpa Kagyu ('brug pa bka' brgyud) school had already been established, and founded the Cheri Monastery in 1619 at the north end of the Thimphu valley. In 1629, he founded his first fortress, Simtokha Dzong, near Thimphu at a place where control could be exerted over traffic between the Paro valley to the west and Trongsa valley to the east.
Over his 35 years as the temporal and spiritual ruler of Bhutan, Shabdrung Ngawang Namgyal repelled a series of Tibetan invasions and overcame internal opposition to unify the country for the first time in its history.
On seven occasions between 1616 and 1679, Tibet launched war against Bhutan, first under the Tsangpa king and, after 1642, under the central Gaden Photang ([dga' ldan pho brang]) government newly established by 5th Dalai Lama, Ngawang Lobzang Gyatso (ngag dbang blo bzang rgya mtsho) [1617-1682].
So important was the Shabdrung Ngawang Namgyal to the stability of Bhutan during this period that his death was kept secret. In 1651 his closest aids announced that Shabdrung had entered strict retreat - and they continued to maintain that he was "in retreat" like this for more than 50 years issuing edicts in his name until 1705. (Source Accessed Jan 27, 2023)
