Alcestis was a princess famous for her unconditional love and heroism
The Impossible Challenge
Alcestis was the most beautiful of the three daughters of Pelias, King of Thessaly.
When she was of an age to marry, several princes and kings appeared to propose, but Alcestis refused all of them.
Pelias, knowing that the constant denials of his daughter to all those powerful suitors could threaten his position, set a test to discover who would be the most suitable husband:
Alcestis was to be the wife of the first man to yoke a lion and a boar to a chariot.
The Sacrifice of Alcestis
With the aid of Apollo, a neighbouring king named Admetus succeeded in this seemingly impossible task.
But at the wedding, Admetus forgot to make the necessary sacrifice in gratitude to Artemis, the goddess of the hunt, and so he found his wedding bed full of snakes, an implication that he had to die.
Once again Apollo came to the king's assistance and persuaded the Fates to spare Admetus' life. The Fates agreed, but asked for the life of another person related to Admetus in return. As no one, not even his parents, would die on Admetus behalf, Alcestis gave her life for him.
The Redemption of Alcestis
The gods, impressed by Alcestis' sacrifice, wanted to honor the princess' unconditional love and heroism. So they decided to redempt
Alcestis' soul sent the Greek hero Heracles and restore her to Admetus, younger and more beautiful than ever.
The couple continued to live happily ever after and they had three sons, who later took part in the Greek expedition against Troy.
Sources"Alcestis" by Eurypides
The "Symposium" by Plato