Shimazu Yoshihiro (島津義弘 ; August 21, 1535 - August 30, 1619), also cited as Shimazu Tadahira (島津忠平) and known as Hyogo no kami, was the second son of Shimazu Takahisa and the 17th head of the Shimazu clan. He was the father of Shimazu Hisayasu and Shimazu Tadatsune (who would later change his name to Iehisa, not to be confused with Yoshihiro's brother).
From a young age he demonstrated many qualities and served in many of his brother Yoshihisa's military campaigns. During the Battle of Kizaki, in 1572, 300 of Yoshihiro's men defeated the three thousand soldiers of Itō Yoshisuke, in what is called the "Okehazama of the Kyūshū".
He fought to secure Shimazu supremacy over Hyūga province in 1577, and participated in the battles of Takabaru (1576), Mimigawa (1576), Minamata (1581), and Hetsugigawa (1587). Yoshihiro was appointed daimyō following the submission of the Shimazu to Hideyoshi in 1587.
He led 10,000 men in the first Korean campaign (1592-93) from his ship Kotaka-maru, and during the second Korean campaign he fought in the battles of Namwon and Sacheon. At the beginning of the first Korean campaign, a number of servants, including his brother Toshihisa, protested the call to arms and so Yoshihiro had to punish them.
He played an important role in kidnapping Korean potters who were brought to Satsuma as prisoners of war. This increased the trade of the province, thanks to the new style of pots, called Satsuma-yaki.
During the Battle of Sekigahara in 1600, according to the Edo period novel Rakusuishū (『落 穂 集 ), Yoshihiro was supposed to take Tokugawa Ieyasu's side, but was humiliated by Torii Mototada upon arrival at Fushimi Castle and took Ishida Mitsunari's side.
However recent research has indicated that Yoshihiro took Mitsunari's side from the very beginning of the campaign, before Mōri Terumoto declared war in July, and Yoshihiro carved out an important role as a member of the generals on Mitsunari's side, and persuaded Uesugi Kagekatsu to ally with them.
As reported by one of Yoshihiro's subordinates named Kando Kutarō, Yoshihiro was a close friend of Mitsunari, but their relationship was distorted by novelists of the Edo period; these recounted how Mitsunari had not listened to any of Yoshihiro's plans, including the notorious surprise night attack the day before the actual battle.
On the day of the battle Yoshihiro and his troops of 1500 samurai simply presided over their area and did not fight. After the rest of Mitsunari's allies were routed, Yoshihiro was stormed by at least 30,000 of Ieyasu's soldiers.
Widely outnumbered, Yoshihiro tried numerous times to get at Ieyasu himself, but after Shimazu Toyohisa convinced him not to die needlessly Yoshihiro decided to retreat.
His troops simulated a mock retreat called Sutegamari (捨 て 奸) when a number of men died maintaining a position and repelling attacks, until the arrival of the main body where Ii Naomasa was wounded. Toyohisa and most of the soldiers under his command sacrificed themselves allowing Yoshihiro to retreat.
After repelling the pursuit, he and his wife repaired to Sumiyoshi of Settsu Province and returned to Satsuma Province.
The Japanese historian Shiramine Jun has studied why the Shimazu clan behaved unwisely: Yoshihiro would be involved in the power struggle between Shimazu Yoshihisa and Ijuin Tadamune, which led Yoshihiro to lose the support of Yoshihisa who did not give him support during the Sekigahara campaign.
After recognizing why and how Yoshihiro behaved on the battlefield, Ieyasu ensured that the Shimazu clan maintained its rule and allowed Yoshihiro's son, Shimazu Tadatsune, to succeed him. Receiving permission from the Shogunate to launch a punitive expedition against the Ryūkyū Kingdom, Yoshihiro and Tadatsune acted in 1609.
He is said to have fought in 52 battles during his lifetime and was a skilled commander.
Yoshihiro retired to Sakurajima and began teaching the younger generation. He died in 1619 and many of his servants who had fought alongside him followed him by committing suicide.