Born in 1535 as the second son of Shimazu Takahisa, patriarch of Satsuma. His elder brother Yoshihisa became the 17th Shimazu head, while Yoshihiro served as the spearhead of their armies. At the Battle of Kizakibaru in 1572, he crushed Ito Yoshisuke's vastly larger force using the "sutegari" rearguard sacrifice tactic. At Mimigawa in 1578, he annihilated the great army of Otomo Sorin in Kyushu's largest battle, dramatically accelerating Shimazu expansion. After submitting to Hideyoshi, he participated as a senior commander in the Korean invasions (1592–1598). At the Battle of Sacheon in 1598, with roughly 7,000 troops he routed a Ming-Korean force many times larger; the Ming named him "Demon Shimazu" in their records. At Sekigahara in 1600, fighting for the Western army, he executed the legendary "Shimazu no Nokiguchi" fighting retreat—charging directly through Tokugawa's encircling army rather than fleeing—while his nephew Toyohisa and others sacrificed themselves holding the rear. Yoshihiro escaped miraculously to Satsuma. He died in 1619 at age 85.