The battle of Lade took place during the Ionian Revolt in 494BC. It was a naval battle between an alliance of Ionian cities and Darius I of Persia.
Greek cities of Asia Minor were dissatisfied with the tyrants appointed by Persia to rule them. The tyrant of Miletus, Aristagoras managed to incite the whole of Ionia into rebellion.
In 498BC the Ionian Revolt had started and over the next three years it spread and there were battles at Ephesus and Pedasus.
This was followed by a stalemate for the rest of 496BC and 495BC.
In 494BC the Persian army and navy decided to make way to the centre of the rebellion Miletus.
The Ionians were to leave the defence of Miletus to its own citizens, while they decided to defend it by sea.
The Ionian navy gathered at the island of Lade off the coast of Miletus with a fleet of around 350 ships.
The Persian navy attempted to persuade members of the Ionian fleet to defect, but this at first failed; however later the Samian members of the Ionian fleet were to accept, maybe due to the Ionian fleet being outnumbered. The Persian fleet totalled some 600 ships.
As battle commenced between Ionia and Persia, the Samians sailed away. Seeing this others followed and the Ionian fleet collapsed.
The Persian fleet had triumphed at the Battle of Lade and the Ionian Revolt was effectively over.