During a portion of that time Alexander contended with success against the Thebans, and maintained his ascendency in Thessaly. But before the battle of Mantineia in 362 B. C., he had been reduced into the condition of a dependent ally of Thebes, and had furnished a contingent to the army which marched under Epaminondas into Peloponnesus. During the year 362-361 B. C., he even turned his hostilities against Athens, the enemy of Thebes; carrying on a naval war against her, not without partial success, and damage to her commerce.[419] And as the foreign ascendency of Thebes everywhere was probably impaired by the death of her great leader Epaminondas, Alexander of Pheræ recovered strength; continuing to be the greatest potentate in Thessaly, as well as the most sanguinary tyrant, until the time of his death in the beginning of 359 B. C.[420] He then perished, in the vigor of age and in the fulness of power. Against oppressed subjects or neighbors he could take security by means of mercenary guards; but he was slain by the contrivance of his wife Thêbê and the act of her brothers:—a memorable illustration of the general position laid down by Xenophon, that the Grecian despot could calculate neither on security nor on affection anywhere, and that his most dangerous enemies were to be found among his own household or kindred.[421] The brutal life of Alexander, and the cruelty of his proceedings, had inspired his wife with mingled hatred and fear. Moreover she had learnt from words dropped in a fit of intoxication, that he was intending to put to death her brothers Tisiphonus, Pytholaus, and Lykophron—and along with them herself; partly because she was childless, and he had formed the design of re-marrying with the widow of the late despot Jason, who resided at Thebes. Accordingly Thêbê, apprising her brothers of their peril, concerted with them the means of assassinating Alexander. The bed-chamber which she shared with him was in an upper story, accessible only by a removable staircase or ladder; at the foot of which there lay every night a fierce mastiff in chains, and a Thracian soldier tattooed after the fashion of his country. The whole house moreover was regularly occupied by a company of guards; and it is even said that the wardrobe and closets of Thêbê were searched every evening for concealed weapons. These numerous precautions of mistrust, however, were baffled by her artifice. She concealed her brothers during all the day in a safe adjacent hiding-place. At night Alexander, coming to bed intoxicated, soon fell fast asleep; upon which Thêbê stole out of the room—directed the dog to be removed from the foot of the stairs, under pretence that the despot wished to enjoy undisturbed repose—and then called her armed brothers. After spreading wool upon the stairs, in order that their tread might be noiseless, she went again up into the bed-room, and brought away the sword of Alexander, which always hung near him.