There are many types of sea mythology. These range from mythological monsters to good and bad omens via sunken cities and ghost ships. Sea monsters perhaps make up the bulk of sea-related mythology and range from the leviathan to the sirens. While sea mythology is linked to water mythology, it does not include any mythologies linked to water supplies, lakes, ponds and rivers, but only to the open seas and oceans with salty water.
Any polytheist group with access to the sea created a sea mythology. Often central to these mythologies were gods and goddesses. In Greek and Roman mythologies, gods such as Neptune and Poseidon were central to their myths. Another sea deity is Sedna of Inuit mythology, although her nature and name change from Inuit group to Inuit group. Other sea deities include Atlacamani, the goddess of oceanic storms in Aztec mythology, and the Ainu God Repun Kamui.
Sea monsters also crop up time and time again in sea mythology. One example is the Leviathan, which is a large sea monster synonymous with whales in modern Hebrew. Another example is the siren, who lures men with her beautiful songs only for the men’s ships to get wrecked on rocks. The siren is linked to the mermaid, a half-human, half-fish creature, which is the symbol of both Warsaw and Copenhagen. Mermaid-like creatures pop up in a number of sea mythologies including as the Aycayia in Neo-Taino culture and the Jengu of Cameroon.
There are innumerable myths surrounding ghost ships. Some of them are more realistic than others. One of the most famous is the myth of the Flying Dutchman as seen in the second and third ‘Pirates of the Caribbean’ movies. The Flying Dutchman is said to appear in storms as a harbinger of death. The Mary Celeste appeared to be a 19th-century attempt at making a ghost ship as she sailed unmanned towards Spain with her cargo and supplies intact, but not a soul on board. There are other ghost ships in sea mythology including Caleuche of Chilota mythology and the Lady Lovibond.
Since Plato’s mention of Atlantis, there have been myths about cities under the sea. These are both myths about lost civilizations and about underwater cultures. The myth of the sunken city may have been based on the fate of Heike, which sank into the sea in 373 BC. Much energy has been put into finding Atlantis and other sunken cities.
There are a number of folk lore stories and folktales that fall under the umbrella of sea mythology. For example, killing an albatross, according to some sailors, is a sure sign of doom. Jonah is another sea-related myth, in which a person who brings bad luck to a ship is called a Jonah.