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The ambush at Honnō-ji, where Akechi Mitsuhide turned on his lord Oda Nobunaga, marked a significant turning point in Japanese history. Mitsuhide's carefully planned betrayal unfolded on June 21, 1582, as Nobunaga was resting at the Honnō-ji temple in Kyoto. The unexpected assault caught Nobunaga off guard, leading to his demise and altering the course of Japan's unification process.