One of the most popular ones tells a story about a German couple. During their romantic stroll on a sunny day, a girl noticed blue flowers and asked her companion to pick them up for her. The flower grew on a steep edge of a nearby river, and unfortunately, the boy fell into the river while trying to pick it up, and drowned. Before submerging, he asked the girl not to forget him, and thus the name of the plant came from.
Another German tale states that when God was naming all living creatures, he forgot about one small, blue-flowered plant, that called to him “Forget-me-not, o Lord!”, to which God replied it shall be the plant’s name.