<p><pre><code>   This puzzles me to no end.
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The answer is economics. When you want to sell a product, it makes sense to fine-tune it as much as possible to the largest, most profitable market, and then re-use the product infrastructure (e.g. production, design, marketing, delivery) to other markets.<p>For a very long time, starting with the British empire, the  largest, most affluent market has been English speaking, and since the end of WWII it was the US.<p>This lead to the emergence of a US-focussed music industry that resells its goods in the rest of the world . A similar phenomenon is at play in other domains like films. As US customers can always easily access products tailored to their preferences, which includes a strong preference for English-language lyrics, it has become economically essentially impossible to be globally successful with (non-instrumental) pop music that is not sung in English. This is a self-reinforcing phenomenon.<p>Interestingly, the dominance of English as voice of pop-music, evaporates as soon as instrumental music is considered: Techno, House, DnB, Dubstep etc shows no dominance of native speakers of English.<p>For a variety of reasons, I expect that English will not be as dominant in the future:<p>- Rise China as biggest, most affluent unified market for pop-music. This will lead to a preference of the Chinese customer for music. This market will be so large and lucrative as to compensate for the lack of Chinese as second-language, which is powerful for English.<p>- The massive lowering of the cost of music production, marketing and (in particular) distribution. The more cheaply we can produce music, the more it makes economic sense to target niche markets.