This dish is a relative of good old fish and chips, which is not as British as one might think. They share origins in a dish beloved of the Shahs of Persia some 1500 years ago - sikbāj - sweet and sour stewed beef. This later made its way around the Arabic world, with fish replacing beef in Christian parts. The amazing history is told by Prof Dan Jurafsky on his blog, 'The Language of Food'.
Dan writes: "The word escabeche came to Spanish from Catalan, which acquired it from its neighbour, Occitan, who got it from the Genoese, who stole it from the Neapolitans, and so on, back eventually east to the Arabic of Baghdad and the Persian of Ctesiphon." And the story continues with the Jews being expelled from Spain and Portugal and going to northern Europe, taking their fish dishes with them. Finally, in England, Belgian frites were married with battered and fried fish doused with vinegar: fish and chips.