This paper explores the agency of the environment (malaria forests) and agrarian culture (shortage of labour, migration, and the politics of little kingdoms) in the organization of territory along the Anglo-Gorkha frontier in early colonial north India. Historically, dense malarial forests restricted access to this frontier at a time when intense efforts were being made by recalcitrant little kingdoms and landed magnates to extend cultivation. Labour too was in short supply. Consequently a shifting forest-field mosaic of agrarian territory emerged from the uneven interactions between ecology, local power, and labour supply. Together, these environmental and human factores combined to impact the layout, extent, and architecture of administrative divisions along the Anglo-Gorkha frontier causing them to shift, overlap, and break up. Such a scenario of spatial fluidity expressed in the form of patchy, ill-defined administrative divisions persisted when these areas came under the authority of the British East India Company and the Himalayan kingdom of Gorkha (present-day Nepal). It may be argued that these spatial dynamics, long ignored by historians of this frontier, provided an important set of circumstances that ultimately led to the Anglo-Gorkha war of 1814-1816. This war led to the defeat of Gorkha and the formal demarcation of the present Anglo-Nepal boundary which, it was hoped, would permanently fix the adjoining territories of the two states along this fuzzy frontier.