Thanks. I've started reading this, which has a lot of interesting ideas in it, in particular this hypothesis:
“Yet Edwin G. Pulleyb-lank has argued that the prototype for the Phoenician alphabet, the ancestor of all other Western alphabets, was the set of Chinese characters known as the heavenly stems and earth branches which today are a cycle of calendrical signs, but in the second millennium BC were an alphabet of initial and final consonants used in a compound script together with pictographs, ideographs and logographs. China therefore invented the principle of the phonetic alphabet, but did not develop it, and in fact eliminated it in her mature script. The West, on the other hand, did not invent the principle, but developed it, by eliminating all other elements in script and by adding the Greek invention of the representation of vowels.”
However, I'm still looking for a good general outline of the historical narrative, without so much admittedly very interesting philosophical and cultural detail.