As a longtime lover of Mexican corridos AND of Anglo-American broadside ballads, this news interests me. I suspect the more we look, the more we'd find that all, or most all ballad traditions, like those of Britain, the United States and Mexico, got a big boost from printing as soon as the press became widely available.

Broadsides were the most far-reaching type of printed ballads, being bought for pennies (or centavos?) and taken home, passed around, learned and sung by an increasingly literate population -- mostly urban, though some broadsides were hawked in rural areas as well. Ballads were occasionally distributed in other printed forms too -- as printers' samples, as fillers in newspapers, and so on.

And so an oral form turned into a printed one, making possible rapid, widespread distribution of those ballads of the Mexican revolution as well as many others -- any song that made a good story was fair game. The parallel effect was that strictly oral circulation began to decline, and became less of a factor as ballads went into print and achieved, or originated as, standardized versions.

There are good book-length studies of the Anglo-American broadside ballad, but as far as I know none that are cross-cultural. A comparative history of broadsides in English, Spanish, French, Italian, German, Slavic, Turkish, you name it -- that would be an interesting study. Bob