Last time ABC Wednesday was on the letter Q, someone asked, “Why does U usually follow Q in English-language words?” And the answer was simple to find, but mighty difficult to explain.
As is noted here, it’s because modern English evolved from the Phoenicians to the Greeks to the Etruscans to the Romans.
Like the Greeks, Latin had only the one k sound. As a result, over time kappa was dropped, koppa evolved into q, and gamma into c (these changes explain why Greek words spelled with k have their Latin equivalents spelled with c). The Romans used q only before u, though the combination was actually written as qv, since v was a vowel in classical Latin, to represent the kw sound that was so common in the language.
If we move on about a thousand years, we find that Old English had the same sound, but represented it by cw, since q had been left out of their version of the alphabet (so queen in Old English was spelled cwen, for example). French, however, continued the Latin qv, though by now written as qu. After the Norman Conquest, French spelling gradually took over in England, eventually replacing the Old English cw by Latinate qu, though this change took about 300 years to complete.
In other words, it’s because English is an evolving, bastardized language. Or, blame the French.
I like the answer here as well: “As for why q is always written with a u in Latin itself… The ‘u’ part is actually the easiest to understand, as its pronunciation approximates the glide sound that ‘w’ represents in the ‘kw’ cluster. What’s harder to understand is why Latin chose to have 2 separate symbols for the ‘k’ sound (the other is c; they never used ‘k’). It’s also amusing that English adopted all 3 symbols (q, c, and k). One of those accidents of history, I guess.”
Helping the Daughter with her spelling reminded me that, linguistically, the letter C has no function that isn’t being rendered by the K or the S.
In other words, expecting rationality in the development of the English language is…totally irrational!
There is even debate as to whether, typographically, there should be a qu glyph – i.e., the letters joined as if they were one. I’ve sometimes seen them written as though aligned.
Here’s a video that will enlighten the issue not at all.