Motonari was raised into the wealthy seafaring Mori family, fighting to expand his borders against the Amako Clan and the Ouchi Clan. In 1555, his first major conquest, was fought at the Battle of Itsukushima against the Sue Clan led by Sue Harukata. Harukata originally served under the Ouchi nation, but became a daimyo and attacked the Mori lands. In a naval battle, the Mori proved their control of the seas by cutting off the heads of Harukata and Sue Nagafusa. In the 1560s, Motonari stamped his control over the Amako by defeating them at Gassantoda Castle and Amago Haruhisa dropped dead. Motonari, however, wanted a break from the conflict, and went into hiding. However, Haruhisa's sons and grandsons united in their opposition by joining forces with the Toyotomi in their invasion of Chugoku. But the Tachibana Clan, vital as an ally of the Toyotomi, surrendered to the Mori and the invasion was beaten back. Motonari became friends with Tachibana Muneshige, a young child and the head of the family. He proposed that three arrows, each representing Motonari, Muneshige, and his wife Tachibana Ginchiyo, and how they would not break easily. This encouraged the Tachibana and Mori to ally against the Oda clan. However, Motonari faced defeat at the Battle of Kizugawaguchi. He repelled the first Oda fleet led by Kuki Yoshitaka, but in the second battle in 1579, his forces were defeated for good. His last battle was at Yamazaki, where he beat off the Kani Clan, the Oda Clan, the Tokugawa Clan, the Honda Clan, the Hattori Clan, and many others. Though he defeated the alliance of warlords, he died of old age the same year.