Why have Lesotho's mountains helped protect its political autonomy?

Lesotho’s political autonomy is deeply rooted in its rugged geography, which has historically served as a natural defense against external encroachment. Two-thirds of the country consists of mountains, including the Maloti Mountains and the Drakensberg range, which create forbidding barriers that separate the nation from its neighbors.123

In the 19th century, the founder of the Sotho nation, Moshoeshoe, strategically utilized this terrain to protect his people. He established his headquarters at Thaba Bosiu, a sandstone plateau that functioned as a nearly impregnable natural fortress. By retreating to this high ground, Moshoeshoe was able to defend his followers against Boer, British, and other rival forces. This combination of difficult mountain topography and adroit military and diplomatic leadership allowed the Sotho to maintain their independence and resist colonial expansion for much of the 19th century.451