The Black Sea

 The Black Sea has been in the news a lot lately, because it's that major body of water past the eastern end of the Mediterranean that has the Crimean peninsula hanging down into it.  Crimea is part of Ukraine but has been in Russian control for eight years.  The entrance from the Mediterranean into the Black Sea is narrow, with the modern country of Turkey on both sides.  Indeed, "Asia" was considered separated from "Europe" by this passage.  (This doesn't make a lot of sense from a map's perspective, but if you're sailing the eastern Mediterranean it sort of does.)

 

Although the modern tendency is to think of medieval Europe only as happening in the lands of modern western Europe, in fact the regions circling the Black Sea were well known to those further west.  Romania is called that because it was part of the ancient Roman Empire; its modern language is indeed close to French.  Bulgaria was believed to be where the Albigensian heresy originated (which medieval people often called the Bogomil heresy).  Ukraine and Russia provided brides for western medieval kings.  And of course what is now Turkey was Byzantium, home of the Roman emperors (as they styled themselves, as indeed they were in a continuous line from the Roman emperors of antiquity).

Note on the map the almost complete land bridge at the southwest corner of the Sea.  Constantinople (now Istanbul) is located right where a narrow opening, the Bosporus, leads from the broader channel coming from the Mediterranean into the Black Sea.  It is a highly strategic location for a city, but it is also important to note that the break in the land bridge is relatively recent in geologic time.

Coming out of the last ice age, what is now the Black Sea was a freshwater lake, only about two-thirds its current size and appreciably lower than the Mediterranean.  Stone Age people lived along its shores.  Then, sometime around 5500 BC, as the melting glaciers raised sea levels, the waters from the Mediterranean broke through.  What had been a freshwater lake became a substantially larger salt water body.  The old shore line is still there, under water, and shells of freshwater mollusks from below the old shore line show how the Sea used to be.

The breaking of the land bridge would have been a sudden, cataclysmic event, like a dam breaking.  There are numerous legends in the Middle East of a sudden, terrible flood (including the story of Noah in the Bible, and the Mesopotamian epic of Gilgamesh), and the flooding of the Black Sea may be at the origin.

The salt water pouring into what became the Black Sea was heavier than the fresh water and sank to the bottom, leaving a brackish top layer.  Because the area does not have the temperature gradients that cause lakes to turn over, the lowest level of the Sea is poison, without oxygen.  (The same is true of the Caspian Sea.)  That means that ships that sank during classical and medieval times, when there was regular commerce between all the countries surrounding the Sea, are very well preserved.  No marine worms to eat the wood!  Archaeologists are starting to map and study the wrecks (mostly remotely, humans can't go down into the poisonous layer).  Not only the wrecked ships are there, but much of their cargo.

© C. Dale Brittain 2022

For more on  medieval trade and shipping, see my new ebook, Positively Medieval: Life and Society in the Middle Ages.  Also available in paperback.