In Greek mythology, what did Minos ask Poseidon to send from the sea?

In Greek mythology, Minos asked Poseidon to send a white bull from the sea.

Minos wanted divine proof that he should become king of Crete. He prayed to Poseidon, who sent a magnificent white bull rising from the sea. Minos promised to sacrifice it, but kept the animal because of its exceptional beauty. The broken promise led to divine punishment and eventually to the birth of the Minotaur.

The bull is often called the Cretan Bull. It should not be confused with the Bull of Crete captured by Heracles as one of his labors, although the two are connected in many versions of the tradition. After its appearance in Crete, the bull became part of the chain of events linking Minos, Pasiphae, Daedalus, and the Minotaur.

The story illustrates a recurring theme in Greek mythology: a ruler receives a divine sign but suffers when he fails to honor the required sacrifice.