"Adapted from Thucydides' History of the Peloponnesian Wars and Plato's Dialogue with Alcibiades by John Barton 2,500 years ago, the great war between Athens and Sparta began.
It lasted 27 years and involved most of the many Greek states in the Eastern Mediterranean.
These shared a common language and were linked by trade and an ever-changing web of alliance. The History of the Peloponnesian War was written by Thucydides, an Athenian general sent into exile by his countrymen.
He was the first man to attempt an objective history of the political complexities of his time, and to make a model, an anatomy, of political behaviour that, he wrote, may be useful in times to come.
His method was to seek eyewitnesses for what was said and done, and to report all speakers fairly and fully.
When evidence for what was said was lacking or self-contradictory, he did not hesitate to imagine the words which, as he put it, 'the situation seemed to require'. He died before the war ended. His book is unfinished."