No one quite knew who or what the Gullals were till The Mussuck, who had been calling on Mrs. Hauksbee, and prided himself upon picking people's brains, explained they were a tribe of ferocious hillmen, somewhere near Sikkim, whose friendship even the Great Indian Empire would find it worth her while to secure.
Source: wiktionary
Indian hillmen of exceptional intelligence and resource, specially trained in clandestine surveying techniques, were despatched across the frontier disguised as Muslim holy men or Buddhist pilgrims.
Source: wiktionary
A farmer on whose ground there was a little hill, resolved not to let it lie idle, and began at one end to plough it up. The hill-man, who lived in it, came to him and asked him how he dared to plough on the roof of his house.
Source: wiktionary