Aegeus
Aegeus had asked his son Theseus to fly white sails on his return trip from Crete -- in case that he survives his encounter with the Minotaur. Theseus promised to do so.
It so happened that Theseus forgot to do it and he sailed with the default black sails instead. (In some versions of the tale, he claimed that complications about his love interest distracted him.)
Aegeus saw the ship and, heartbroken, jumped off the cliffs into what is now called the Aegean Sea.
Author: GW
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