At Sekigahara (1600), Kuroda Nagamasa served not only as a warrior but as a central figure in diplomatic maneuvering. He worked to bring Toyotomi-allied generals like Fukushima Masanori and Kato Kiyomasa into the Eastern forces, and the secret arrangement for Kobayakawa Hideaki's defection is attributed to his negotiations. He fought at the center of the Eastern forces in the main battle and received Fukuoka-Chikuzen at 520,000 koku. While his father Kanbei (Josui) is said to have aimed at seizing the realm by exploiting Sekigahara, Nagamasa loyally served Ieyasu—making them a contrasting father-and-son pair in the telling.