Causes of the Peloponnesian War

 Sparta’s constant aggression towards Athens

The Spartans were in many ways the most convenient enemies that Athens could have had

The office of Strateges (‘general’ commands both sea and land) was an elected post, normally one from each ten tribes. There were no limits on re-elections. Generals could be fined and deposed of by the Assembly. This happened after the 460’s BC.

Low standard of military security

It was recommended to have a small number of generals with full powers, ‘so that things which ought to be secret can be kept concealed’ (Th.6.72.5)

Breaches of security (this meant less likely to trust each other)

Sparta lost control of allies in the central and northern Peloponnese, this was depended on by Sparta to keep them as a great power in Greece

Without her Peloponnesian allies,  Sparta could not hope to continue sending large armies…