483 BC
Athenian archon Themistocles realises that the Greeks need to be able to beat the Persians at sea. To carry out this strategy, however, Athens needs far more warships (that is to say the newly developed, specialised triremes) than the 70 it has. Themistocles is initially opposed by other Athenian leaders. However, when the state-owned silver mines at Laurium become the site of a rich strike, Themistocles persuades the assembly, instead of "declaring a dividend," to devote the whole surplus to increasing the navy to a proposed 200 ships.