Originally Posted by
Pickles
I was actually thinking of oshizushi when I wrote that, but it was more a jab at the "historical" bit. Don't know for sure, but before refrigeration became available, much of what was eaten in Edo was probably oshizushi, even though it was (and is) possible to haul in some stuff from nearby (Edomae) and serve it raw with whatever rice chemistry you desire.
Yes, but then some time in the early 1800s they changed things in Edo to what is known as edomae or really nigiri sushi. Placing a piece of locally caught fish on a handformed ball of rice. That fish until refrigeration was probably pickled in vinegar, salted or lightly cooked. But it was a great leap forward compared to the traditional fermented sushi, i.e. narazushi that goes back centuries. That stuff is probably more like surströmming, i.e. awful.
Then with refrigeration they started to eat it with raw fish in Tokyo/Kanto.
Oshizushi is also a more modern (i.e. 1700s maybe, just guessing?) variant, I think. The fish is not fermented but you never use raw fish. My understanding is that this was the primary type of sushi in Kansai until some time in the 1900s, possible even postwar period. The traditional variant is to use pickled (and salted?) mackerel. You can even buy it at the airport and it's unrefrigerated.
http://foodfile.typepad.com/blog/2012/09/oshizushi.html