From the above-referenced article:
The history of the Baja fish taco is somewhat murky. It is served throughout the peninsula, a narrow, mostly arid spit of land that extends for almost 800 miles along Mexico's northwestern coast (the state of Baja California occupies the peninsula's upper half). But two spots in the northernmost part of the region—Ensenada and San Felipe, a speck of a town between the parched landscape of the Baja Desert and the warm waters of the Sea of Cortez—claim to have invented the dish. The supporting evidence is anecdotal at best.
Read it all here: http://online.wsj.com/news/articles/S...