One major event in Japan's 16th-century civil war — which is the focus of "Gunshi Kanbei (Strategist Kanbei)," NHK's current Sunday-night drama series — involves the duplicitous warlord Akechi Mitsuhide.

Probably moved by personal jealousy, Mitsuhide betrayed his lord and ally, Oda Nobunaga, by staging a coup d'etat at the Honnoji Temple in Kyoto, on June 21, 1582, according to the Western calendar. The 48-year-old Oda died during the battle — it's believed he committed suicide rather than suffer the ignominy of defeat. Mitsuhide then proclaimed himself 将軍 (shōgun, military commander), a position he held for less than two weeks until falling in battle against another warlord, Toyotomi Hideyoshi.

Mitsuhide's rapid rise and fall spawned the four-character aphorism 三日天下 (mikka tenka, literally three days under heaven), which refers to a short-lived reign or moment of glory that didn't last.