The Black Sea has had many different names throughout its history. Each new people that came to its shores called it differently.
At the beginning of our era, the Scythians called the Black Sea - Tana (dark), in Iran - Ashkhaena (dark). Also the Black Sea in different times was called Khazar, Surozh, Russian, Scythian, Temarun, Saint, Tauride, Ocean, Blue.
There is such a fascinating science - toponymy, which studies the origin of geographical names (toponyms). According to this science, there are at least two main versions of the origin of the name of the Black Sea.
Version one. It was put forward by the ancient Greek geographer and historian Strabo, who lived in the 1st century BC. In his opinion, the sea was named Black by Greek colonists, who were once unpleasantly struck by storms, fogs, and unknown wild shores inhabited by hostile Scythians and Taurians. They gave the stern stranger the appropriate name - Pontos Akseinos - “inhospitable sea”, or “black”. Then, having settled on the shores, becoming related to the sea of good and bright fairy tales, the Greeks began to call it Pontos Evxeinos - “hospitable sea.” But the first name was not forgotten, like the first love...
Version two. In the 1st millennium BC, long before the arrival of careless Greek colonists, on the eastern and northern shores Sea of Azov Indian tribes lived - Meotians, Sindians and others, who gave the name to the neighboring sea - Temarun, which literally means “black sea”. This was the result of a purely visual comparison of the color of the surface of the two seas, now called the Azov and Black. From the mountainous shores of the Caucasus, the latter appears darker to the observer, as can be seen even now. And if it’s dark, it means black. The Meotians on the shores of the mentioned seas were replaced by the Scythians, who fully agreed with this characterization of the Black Sea. And they called him in their own way - Akhshaena, that is, “dark, black.”
There are other versions
From the point of view of sailors, the sea is called “Black” because there are very strong storms, during which the water in the sea darkens. However, it must be said that strong storms are very rare on the Black Sea. Strong waves (more than 6 points) occur here no more than 17 days a year. As for the change in water color, this phenomenon is typical for any sea, not only the Black Sea.
Another name for the Black Sea sounds very ominous - “the sea of dead depths.” Indeed, the waters of the Black Sea have unusual characteristics. The depths of the Black Sea are divided into two levels. Below 150-200 meters there is practically no life here due to the high percentage of hydrogen sulfide contained in the deep layers of water.
Over the years of its existence, the Black Sea has accumulated more than a billion tons of this substance, which is a product of bacterial activity.
According to one version, the very appearance of the Black Sea (7500 years ago) was associated with mass death freshwater inhabitants of the Black Sea lake that was once here. Because of this, reserves of hydrogen sulfide and methane began to accumulate at its bottom. However, scientists do not yet have a consensus on the origin of the huge volume of hydrogen sulfide in the waters of the Black Sea. The approximate amount of hydrogen sulfide in the Black Sea is 3.1 billion tons.
Research recent years also allow us to talk about the Black Sea as a giant reservoir of not only hydrogen sulfide, but also methane. It is the detonation of methane due to movements of lithospheric plates that today explains the strange phenomenon that occurred during the earthquake of September 11, 1927.
Well-known researcher of Crimea, professor-geologist S.P. Popov described this phenomenon as follows: “... during the earthquake, observers of three lighthouses on the western coast of the Black Sea noticed a giant fiery stripe 55 kilometers from the coast over a long distance between Sevastopol and Cape Lucullus.” Subsequent interviews made it possible to establish that the fire was not isolated - observers noticed three explosions.
The sea attracts people with its mystery and inaccessibility. Its inhabitants are often surrounded by a mystical aura; human imagination places the most terrible monsters in the depths of the sea. The names are also surrounded by legends and myths. There is no exact answer why the Black Sea is called black. But there are a lot of interesting options presented by historians, geographers, hydrologists and sailors.
Legends and hypotheses about the appearance of the name
Such a variety of names that were awarded to the sea different peoples, something to be proud of. No other body of water has received such an honor. He was named after geographical location and then paradoxical facts emerged. For example, the Arabs called it Northern, and the Greeks called it Eastern. Residents of the coast made their contribution, bravely defending villages from raids, for which they nicknamed him Kara-Dengiz, inhospitable.
Here are some guesses:
- Black Sea legends colorfully describe some events, and one can’t help but believe that at the bottom lies a heroic sword or a golden arrow, which can be used to divide the world in half, so the sea boils and darkens, trying to throw out a terrible weapon from its depths.
- Another explanation for why the Black Sea was called black lies in its wayward character. Storms, although rare, come suddenly, forcing the water to take dark shade. After this, bales remain on the shore brown algae and dark gray silt.
- The following version belongs to hydrologists, confirming the fact that the main part sea creatures does not fall below a depth of 100 m. Important: the reason lies in hydrogen sulfide permeating the lower layers. Bacteria reign there, feeding on the remains of dead animals and plants.
- Sailors claim that a few hours before a storm, the water at depth sharply darkens.
- There are many reasons why the sea was called the Black Sea. Another version says that the name of the Black Sea was given by Magellan, who saw the expanses raging during a storm.
When was the sea first called Black?
Many people, flying by plane over the surface of the waters, note that they really look black and opaque. It immediately becomes clear why the Black Sea was called that. From photographs from space, it also looks like a dark spot, so the name is quite justified.
Over the centuries, the sea constantly changed its name depending on who was talking about it. There is no certainty about who came up with the idea of calling the Black Sea. According to some sources, the origin was given by the translation of the Greek Pont Aksinsky, inhospitable, black.
Many people wonder why the Black Sea is called black? Is it really black, and what is the reason for this name? The answer to this question can be obtained by flying over it on an airplane - from a height it really looks black, unlike the Mediterranean and other seas. But in fact, the question is rooted far back in history.
And the Bulgarians call him - Black Sea, and the Italians - Marais Nero, and the French - Mer Noir, and the British - Black Sea, and the Germans - Schwarze Meer. Even in Turkish, “Kara-Deniz” is nothing more than “Black Sea”.
Where does such unanimity come from in naming this amazing thing? blue sea, captivating us with its radiant serenity? Of course, there are days when the sea is angry, and then its face darkens to bluish-violet... But this happens rarely, and even then only during difficult times for it winter time.
And in clear weather with early spring and until late autumn the Black Sea is remembered for a long time for its rich blue, turning into light turquoise tones as it approaches the shore... “The sky wants to be beautiful, the sea wants to be like the sky!” – V. Bryusov said poetically about this. And yet, who and when called this sea the Black Sea?
There is such a fascinating science - toponymy, which studies the origin of geographical names (toponyms). According to this science, there are at least two main versions of the origin of the name Black Sea.
Version one. It was put forward by the ancient Greek geographer and historian Strabo, who lived in the 1st century BC. In his opinion, the sea was called Black by Greek colonists, who were once unpleasantly struck by storms, fogs, unknown wild shores inhabited by hostile Scythians and Taurians... And they gave the stern stranger the appropriate name - Pontos Akseinos- “inhospitable sea”, or “black”. Then, having settled on the shores, becoming related to the sea of good and bright fairy tales, the Greeks began to call it Pontos Evxeinos - “hospitable sea.” But the first name was not forgotten, like the first love...
Version two. In the 1st millennium BC, long before the appearance of careless Greek colonists here, Indian tribes lived on the eastern and northern shores of the Sea of Azov - Meotians, Sindians and others, who gave the name to the neighboring sea - Temarun, which literally means “black sea". This was the result of a purely visual comparison of the color of the surface of the two seas, now called the Azov and Black. From the mountainous shores of the Caucasus, the latter appears darker to the observer, as can be seen even now. And if it’s dark, it means black. The Meotians on the shores of the mentioned seas were replaced by the Scythians, who fully agreed with this description Black Sea. And they called him in their own way - Akhshaena, that is, “dark, black.”
There are other versions. For example, one of them says that the sea was so named because after a storm black silt remains on its shores. But this is not entirely true, the silt is actually gray, not black. Although... who knows how all this was seen in ancient times...
In addition, there is another hypothesis about the origin of the name “ Black Sea", put forward by modern hydrologists. The point is that any metal objects, the same anchors of ships, lowered to a certain Black Sea depth, rise to the surface blackened under the influence of hydrogen sulfide located in the depths of the sea. This property was probably noticed since ancient times and, undoubtedly, could have served to assign such a strange name to the sea.
In general, the sea is capable of taking on a wide variety of colors and shades. Let's say, in February-March you can find that the water off the Black Sea coast is not blue, as usual, but brown. This color metamorphosis is a biological phenomenon, and it is caused by the mass reproduction of the smallest unicellular algae. The water begins to bloom, as people say.
IN " color scheme» There are a lot of interesting things in the Black Sea. In all other respects, there are countless amazing and entertaining things...
A sea of fairy tales and mysteries
The Black Sea protects!
The scent of legends is so sweet
The magic of legends is a magnet!
A sea of truths, revelations,
A sea of fiction and secrets,
Sea of thousands of generations
A sea of hundreds of thousands of countries!
Dmitry Rumata “Secrets of the Black Sea”
At different times, the Black Sea had its own names. The Scythians called it Tana, the Iranians - Akhshaena, the ancient Greeks - Pont Aksinsky (Euxine). However, in the language of most peoples the Black Sea has always been "black".
But does it really have that color? Indeed, in clear weather its waters are sky blue or greenish, in cloudy weather they are purple, and at sunset they have a pinkish tint. Why is the sea called black? Where did this name come from? There are several explanations for this.
Strabo's version
One of the most widespread is considered to be the version of the historian Strabo, according to which the Greek colonists nicknamed the Black Pond. Once, having arrived at its shores, they were unpleasantly struck by storms and squalls, as well as by the hostility of the Tauri and Scythians who lived here. Thanks to this, the Greeks gave the sea the name Pont Aksinsky, which means “Inhospitable Sea”, or “black”.
Later, when colonists settled on the coast and became friends with the indigenous people, they renamed it Pont Euxine, or "Hospitable Sea." However, the first name has survived to this day. 
However, in the chronicles of Strabo one can find references to the fact that in ancient times the Black Sea was simply called “the sea”, and in the 10th–14th centuries some Arab and ancient Russian sources called it “Russian”, which was associated with sailors from Ancient Rus'.
Sailors' hypothesis
Like the Greeks, many sailors in ancient times spoke of the sea as “Black” because of the storms during which it darkened. This version cannot be considered reliable because bad weather on the Black Sea it is quite rare, and strong storms occur no more than 15–17 times a year.
In addition, the color change sea water in case of unfavorable weather conditions typical for many bodies of water on the planet. It is believed that sailors could be repelled by the characteristic black silt that accumulates on its coast after storms.
Turkish legend
According to the Turkish version, a heroic sword is hidden at the bottom of the Black Sea, which was thrown into the water according to the last wish of the dying sorcerer Ali. The Turks believed that in an attempt to extract deadly weapons from its depths, the sea became agitated and turned black. 
Another hypothesis is similar to the story of the Greek colonists. They say that Turkish warriors once tried to conquer the population living on the coast, but they met desperate resistance and nicknamed the sea Kara-Dengiz - “black”.
Hydrologists version
An interesting version was put forward by hydrologists who studied the depths of the sea. In their opinion, the sea got its name due to the fact that metal objects (in particular, anchors) raised from its bottom turn out to be blackened. The reason for this lies in the large amount of hydrogen sulfide, which is saturated in water at depths below 150 meters. When it gets on the metal, it covers it with a thin dark coating.
Large accumulations of hydrogen sulfide are associated with the small size of the Black Sea and the difficult exchange of water between it and Atlantic Ocean. The insignificant magnitude of tides and poor miscibility lead to the formation of two layers of sea water - the upper desalinated one, containing a large number of oxygen, and the lower one is more salty and dense, poorly enriched with oxygen.
Hydrogen sulfide formed in the deep layer is a product of the vital activity of microorganisms that, over millions of years, have accumulated millions of tons of colorless gas at the bottom.
Other versions
Some historians believe that the name of the sea is associated with the color designation of the cardinal directions generally accepted in Asia. The north of Asian peoples is black, hence the name of the reservoir located north of Asian states. There is also a hypothesis that the sea was nicknamed Black by Indian tribes (Sindians, Maeotians) who lived on the northern and eastern coasts of the Sea of Azov long before the arrival of Greek colonists. 
The Sea of Azov visually seemed lighter to them, so they gave the name “black” to the neighboring one. Later, the Iranians settled in the habitat of the Meotians, who adopted a similar name, but renamed it in their own way - Akhshaena, or “dark”.