Saint Senara

Her husband, a Breton king, wrongly accused her of adultery and threw her into the sea in a barrel while pregnant.

[5] She was visited by an angel whilst floating in the sea off the westernmost end of Cornwall, and gave birth to a son in the waves, who later became Saint Budoc or an Irish bishop.

[6][7] Due to the striking similarity, the legend's origins possibly lie in Greek mythology and the story of Danaë who was also cast to sea with her son Perseus in a wooden box.

[8][9][10] The mermaid was highly venerated by local fishermen and is said to represent the dual nature of Christ (human and divine).

[11] In Kidd's reimagining of the myths, Senara was originally a mermaid named Asenora who would remove her fish tail to walk on land.