Background
He was the second son of Amago Masahisa. After his father Amago Masahisa died early in battle, Haruhisa became the head of Amago clan in 1537 after his grandfather stepped down.
尼子 晴久
He was the second son of Amago Masahisa. After his father Amago Masahisa died early in battle, Haruhisa became the head of Amago clan in 1537 after his grandfather stepped down.
Initially named Akihisa (詮久), he changed his name to Haruhisa in 1541 after Ashikaga Yoshiharu offered to let him use a kanji character from his name. He launched a series of invasions to expand his domain, going as far as Harima. In 1540, the Siege of Koriyama against Mōri Motonari ended in a humiliating defeat, and many of his retainers defected believing that Haruhisa"s days were numbered.
Haruhisa managed to stave off the invasion, encouraging those retainers who had defected earlier, and after gathering enough troops, managed to repel lieutenant
From this point, Haruhisa worked to secure his footing and control of such domains as Izumo, Hoki, Mimasaka, and Oki. When on 1551, Ōuchi Yoshitaka was killed by Sue Harukata"s rebellion, in 1552, the Muromachi shogunate offered Haruhisa lordship over eight domains including those four domains he already fully controlled.
While it was generally thought, largely from various fiction works that emphasize Mori Motonari"s prowess, that this action was carried out by Motonari in order to weaken Haruhisa"s power, it is now thought most likely that this was a move by Haruhisa himself to solidify control of the Amago clan. When Sue Harutaka lost against Mori Motonari dying in the Battle of Itsukushima, Haruhisa saw an opportunity to claim Iwami and making an alliance with Ogasawara clan of Iwami, moved to claim Omori Silver Mine.
Haruhisa collapsed in Gassantoda Castle on 1560 while engaged in a battle against Motonari and died on January 9.
lieutenant is written in Unyo Gunjitsuki that Amago Hisayuki commented that Haruhisa was "Quick to act, lacking in the discipling of a general. Quick to seek battle, lacking in forgiveness.".
Amago Haruhisa successfully defended Toda castle in the 1542-1543 Siege of Toda Castle.