It has been said that Lesotho was partly named by the French who went there in 1833 as missionaries. Sotho is the noun root of everything related to our nation. The language is Sesotho, I'm a Mosotho, two or more of us are Basotho, and our culture and customs are Sesotho.
The story goes, then, that those guys, wanting to refer to us, simply said Les Sothos, just like they could have said Les Suédois or Les Indiens, or just like an English-speaking person would have said The Sotho, as any of us would say The French, The Xhosas, The Americans. Les Sothos. And that, apparently, is how our country came to be known as Lesotho.