'He conquered all of Greece and Sparta when his father died and he was left in charge of hid kingdom.'
^^ Was the first answer. Which is, without meaning to be to rude, incorrect in so many ways.
Ancient Greece was not a country in the modern sense, it was a loose collection of city-states, of which Sparta is not separate. Sparta is only one of these states, although a prominent one; along with Athens, Thebes, Macedonia and Corinth.