Takenaka Hanbei's Seizure of Inabayama Castle — A Coup of Sixteen Men and the Pride of the Sword

On February 6, 1564, a twenty-year-old military genius named Takenaka Shigefuyu — better known by his common name Hanbei — led sixteen men into the seemingly impregnable Inabayama Castle and seized it from the Saitō clan in what must rank among the most audacious single acts of the entire Sengoku period. The feat was achieved not for personal gain but, according to tradition, as a dramatic gesture of loyal remonstrance against his incompetent lord — an act that placed the values of the sword-bearing class front and center.

Takenaka Hanbei (1544–1579) was the son of a minor lord from Fuwa District, Mino Province. From youth he showed extraordinary talent in military strategy and castle warfare, a gift he would later deploy as the chief adviser (gunshi) to Hashiba Hideyoshi (the future Toyotomi Hideyoshi). Paired with Kuroda Kanbei as the famous "Two Hanbei/Kanbei," he became one of the Sengoku era's most celebrated strategists before his death at thirty-six.

The target of his coup was Saitō Tatsuoki, who had inherited the Saitō domain of Mino Province in 1561 at just fourteen years old. Unlike his formidable grandfather Saitō Dōsan, Tatsuoki showed little aptitude for governance, reportedly neglecting state affairs for wine and pleasure while Oda Nobunaga's armies repeatedly probed Mino's defenses. The clan's retainers grew increasingly alarmed, but their remonstrations were ignored.

Hanbei's plan exploited a simple vulnerability: his younger brother Shigenori was being held inside Inabayama Castle as a hostage. Using the pretext of visiting his brother, Hanbei led his tiny band into the castle. The garrison, unprepared for internal seizure, was overwhelmed before it could mount organized resistance. Tatsuoki, who happened to be outside the castle, found himself locked out of his own stronghold.

For roughly half a year, Hanbei held Inabayama Castle and publicly demanded political reform. Then, having made his point, he surrendered the castle back to Tatsuoki in August 1564 and retired to his family's Bodaisan Castle — asking nothing in return.

This gesture — dramatic, selfless, and ultimately futile in preventing the Saitō clan's eventual destruction by Nobunaga — became Hanbei's founding legend. For contemporaries and later generations alike, it embodied a particular samurai ideal: the sword (and by extension, military power) deployed not in pursuit of personal ambition but as an instrument of moral remonstrance. The act resonated with the Confucian-inflected values of warrior culture, in which loyal protest against a bad lord was a duty as serious as martial valor.

Mino Province, where this drama unfolded, was home to the Seki swordsmiths — the largest concentration of blade-makers in medieval Japan, whose "Seki-mono" swords were prized for their practicality across all social strata. The Inabayama coup occurred at the peak of Mino-den production, in a region where swords were woven into the fabric of daily military life. Whatever blade Hanbei personally carried remains historically unverified, but local tradition in Gifu holds that he favored Seki-forged swords — consistent with a Mino warrior of modest but proud lineage.

Hanbei subsequently entered the service of Hashiba Hideyoshi, contributing his tactical genius to the western Japan campaigns until his death from illness at the siege of Miki Castle in 1579. Inabayama Castle, rebuilt by Nobunaga as Gifu Castle, still crowns the peak of Mount Kinka in Gifu City, a monument to both Nobunaga's ambitions and the remarkable young strategist who took it with sixteen men.