The military history of Bhutan begins with the Battle of Five Lamas in 1634, marking Bhutan's emergence as a nation under the secular and religious leadership of Zhabdrung Ngawang Namgyal. Before Bhutan emerged as a separate nation, it remained on the periphery of Tibetan military and political influence. The region that became Bhutan was host to several battles and waves of refugees from turmoil in Tibet. After its founding, Bhutan was invaded numerous times by outside forces, namely Tibetans, Mongols, and the British. Bhutan meanwhile invaded its traditional tributaries in Sikkim, Cooch Behar, and the Duars.
Bhutan effectively ceased all international military hostilities in 1865 under the Treaty of Sinchula after its defeat by the British Empire. Under the terms of the subsequent Treaty of Punakha in 1910, Bhutan effectively became a British protectorate. Bhutan has maintained this status with India under Bhutan–India relations since 1949 and has modernly engaged only in limited domestic operations against Indian separatist groups.
Ancient history
The earliest military history of Bhutan generally related to that of Tibet. Between the 9th century and Bhutan's emergence as a nation in the early 17th century, Bhutanese territory hosted Tibetan military settlement, waves of refugees from religious and political strife in Tibet, and some conflict between Tibetan and Indian people.
In 824, Tibetan King Tritsun Desten (r. 816–836), also called Raelpachen and grandson of Trisong Detsen, went to war with an Indian ruler in Bhutan, driving him out. Tibetan troops who remained in Bhutan were called Milog, meaning "those that will not return." The region they settle were referred to as Tshochhen Gyed. Its eight parts or divisions were Wang, Be, Med, Kawang, Chang, Thi, Thim, and Lar. In 836, Tritsun Desten was murdered by agents of his brother Langdharma. Tibetans sought refuge in Bhutan from ensuing political and religious upheaval during the reign of Langdharma (836–842). After Langdharma's assassination in 842, Tibetans continued to flee to western Bhutan, the Ngalop homeland. The centuries that followed, known as the Era of Fragmentation, were characterized by their lack of political cohesion. During much of this period, the dominant Bhutanese polity was the Kingdom of Bumthang.
In the late 9th century, ethnic Tibetan forces expelled Indian princes from parts of modern Bhutan. Tibetans in this period and location developed the roots of Ngalop culture.
By the 11th century, Tibetan-Mongol forces occupied the whole of Bhutan. More waves of Tibetans sought refuge in Bhutan from religious persecution. Charismatic lamas became the de facto leaders of regions in western Bhutan. In the 1360s, another wave Tibetan Gelugpa monks fled to Bhutan.
Early history
The military history of Bhutan as a nation begins with warfare between founder Zhabdrung Ngawang Namgyal, himself a Tibetan refugee, and rulers of Tibet. Between 1627 and 1634, a series of wars culminated in the Battle of Five Lamas, the Zhabdrung emerging victorious. Military incursions from Tibet and the Mongol Empire continued through 1714. As Bhutan gained its own measure of regional power in the late 17th century, it invaded neighboring kingdoms in Sikkim, Cooch Behar, and the Duars.
In 1616, Zhabdrung Ngawang Namgyal, facing arrest and following visions in which it is said that the chief guardian deities of Bhutan offered him a home, left Tibet to establish a new base in western Bhutan, founding Cheri Monastery at the head of Thimphu valley. During the Bhutanese period of theocratic rule (1616–1907), there was no regular standing army. The bow and arrow were among the principal means of arming the population during frequent upheavals and invasions. During times of crisis, the government raised militias from among local lords' retinues, all commanded by one dapon ("arrow chief"), a title used through modern times.
Around 1627, the Zhabdrung built Simtokha Dzong at the entrance to Thimphu valley. From this dzong he exerted control over traffic between the powerful Paro valley to the west and Trongsa valley to the east. In 1627, during the first war against Karma Tenkyong of Tibet, Portuguese Jesuit Estêvão Cacella and another priest were the first recorded Europeans to visit Bhutan on their way to Tibet. They met with Ngawang Namgyal, presented him with firearms, gunpowder and a telescope, and offered him their services in the war against Tibet, but the Zhabdrung declined the offer. After a stay of nearly eight months, Cacella wrote a long letter from the Chagri Monastery reporting the travel.