This article posits that friendship has been a particularly fertile and creative category against the backdrop of imperial expansion and consolidation in the Himalayas. As a small but strategically perceived sovereign Himalayan country, Bhutan's history through the last centuries has been marked simultaneously by imperial and post-colonial asymmetries of power. The term “friendship” is deployed as a key diplomatic category in Bhutan's most significant relationship, that with its much larger neighbour India. However, the origin of this friendship is always traced back to the mid-twentieth-century post-colonial period. In contradistinction to this, I constellate a much longer history of this friendship with a special focus on the landmark 1910 Treaty of Punakha between Bhutan and Britain, which was a key turning point in Bhutan's relations with its southern neighbour (British India at the time). Scholars typically state as a matter of fact that in the year 1910, with the initiative of Political Officer Charles Bell, a treaty was signed between Britain and Bhutan that placed Bhutan's external relations under the guidance of Britain. This present work is situated within the oeuvre of critically rereading imperial sources and evaluating their historical legacies, and is the first detailed scholarly analysis of why this treaty was significant and how it came to be signed. I identify the factors that were at work in how and why the 1910 friendship treaty was realised for imperial British purposes—the interpersonal friendships fostered by the British Political Officers; the threat of China as an Other; and the representation of material and ideational advantages from associating with an imperial power. In making this argument, I analyse the role played by the vocabulary of friendship and draw upon primary archival sources to illustrate the factors that were at work as well as the dissonance between the archival and public rationales provided by Political Officer Bell. The 1910 treaty was signed at a watershed moment after the then-recent installation of a monarchy in Bhutan in 1907, and against the great game backdrop of Qing activities in Tibet and British interests in the region; throughout the twentieth century, the impact of this friendship treaty was of paramount significance, and its shadow continues into the twenty-first century.