How expensive was wine in medieval times and was there a similar variation in price between average, good and excellent wines as we see in the modern era? Would you classify wine as luxury finished trade-goods (what about olive oil…)? – Thank You, RSAFan.

Borrowing from 

Kenneth Hodges’ Medieval Price List:

Wine:
  Best Gascon in London         4d/gallon   1331        [2]     194
  Best Rhenish in London        8d/gallon     "          "       "
Wine:
  Cheapest                      3d-4d/gal   Late 13 cen [3]     62
  Best                          8d-10d/gal    "          "       "

So yes, there are variations, both in terms of overall vintage quality and in terms of desirable regional vintages. (It gets a little complicated by the fact that wine was one of those things where you tended to see royal monopolies, privileges, and excise taxes the most, so for example Hodges notes that there were “three London taverns with the exclusive right to sell sweet wines (hippocras, clarry, piments)” in the 1360s, which naturally would have raised the prices of those drinks considerably. For reference: 4 pence a gallon in 1331 works out to £11 a gallon in today’s money.

As for how to classify those things, it’s tricky. On the one hand, they’re not untouched natural resources (that would be grapes), and they’re clearly more value-added than grape juice. On the other hand, there’s a limit to how much value you can add – it’s not like manufacturing steel or cloth, there’s only so many steps between vine and table. And historically, the wine for wool trade tended to favor the economic development of the latter…