XVII. When the Achæans again assembled at Argos to hold a conference there, and Kleomenes started to go thither from Tegea, men's minds were full of hope that peace would be finally established. But Aratus, who had already settled the main points of his treaty with Antigonus, and feared that Kleomenes would either by persuasion or force bring the assembly over to his views, sent to him demanding either that he should take three hundred hostages for his safety and come to the conference alone, or else meet them with his army outside the walls at the gymnasium called the Kyllarabium. Kleomenes on hearing this said that he had not been properly treated; for Aratus ought to have warned him of this at once, not have waited till he was almost at the gates of Argos and then expressed suspicions of his honesty of purpose and driven him away. He sent a letter to the assembled Achæans, containing bitter invectives against Aratus, and as Aratus replied by maligning him in a public oration, he broke up his camp and sent a herald with a declaration of war, not to Argos, according to Aratus, but to Ægium, in order to take the Achæans by surprise. The Achæan cities were all ripe for revolt, as the populace hoped for a redistribution of the land and cancelling of debts if they joined the Spartans, while the leading men were all jealous of the power and influence of Aratus, and some of them hated him as the traitor who was bringing the Macedonians into Peloponnesus. Relying upon the prevalence of this feeling Kleomenes invaded Achaia, took Pellene by surprise, and drove out the garrison and the Achæan inhabitants. Soon afterwards he captured the cities of Pheneus and Penteleum. The Achæans of Corinth and Sikyon now began to fear that his partisans were plotting to deliver up those cities to him, and in consequence sent their cavalry and foreign mercenaries away from Argos to guard those towns, while they themselves proceeded to Argos to hold the Nemean festival there. Kleomenes, rightly judging that his appearance at a time when the city was full of a disorderly crowd of people who were come to attend the feasts and games would produce great confusion, marched up to the walls by night, seized the place called the 'Shield,' which is just above the theatre, and is very difficult of access, and so terrified the citizens that no one attempted to offer any resistance. They willingly agreed to admit a Spartan garrison, to give twenty of their chief men as hostages for their loyalty, and to become the allies of the Lacedæmonians, acknowledging their supremacy.