his delay and broke the siege to continue westward along the Nakasendō. He would still, however, only rendezvous with his disappointed father's forces late in the day on 21 October, after the Battle of Sekigahara had been fought and decided. Tōhoku theatre Uesugi Kagekatsu's uprising began in earnest even before the Western Army's proclamation, but Date Masamune and Mogami Yoshiaki began responding to hostilities even before the declaration of war. The Satake clan of Kubota Domain declared neutrality in the conflict due to a secret treaty with the Uesugi and the divided sympathies of clan head Satake Yoshinobu. Maeda Toshinaga also declared for the Tokugawa, but was initially blocked from supporting the campaign due to an internal conflict with the pro-Western faction within the Maeda clan led by his brother Toshimasa in Noto Province. Toshinaga eventually laid siege to Daishōji Castle on 7 September, prompting the suicide of the garrison commander and Toshimasa's capitulation. Keichō Dewa Campaign The northern campaign in and around Dewa province, known as the Keichō Dewa Campaign, was the key flashpoint providing the casus belli for the Sekigahara Campaign at large, and largely consisted of actions by the Uesugi clan against the combined forces of Mogami Yoshiaki and Date Masamune in an unsuccessful attempt to draw Ieyasu's troops northward from Edo. In the course of responding to the Uesugi clan's mobilisation prior to the declaration of war, Date Masamune seized Shiroishi Castle south of Sendai from the Western Army-aligned Uesugi army in a short siege from the 18–19 August. Masamune's 20,000 troops under Katakura Kagetsuna, Oniniwa Tsunamoto and Yashiro Kageyori attacked Matsukawa, defended by 6,000 defenders under Honjo Shigenaga and Suda Nagayoshi, on October 6, but were repelled. Uesugi Kagekatsu nominated Naoe Kanetsugu to lead the campaign against the Date and Mogami. The three-division invasion of Mogami territory was launched on 14 October with the aims of taking Yamagata Castle, the 10,000-strong headquarters of Mogami Yoshiaki. Kanetsugu advanced from Yonezawa on 14 October with 20,000 troops of the first division westward towards Yamagata Castle; en route, the Uesugi army besieged Hataya Castle on 18 October, where the garrison of 300 led by Eguchi Gohei fell defending it to the last man. Simultaneously, the 4,000-strong second division under Honmura Chikamori and Yokota Munetoshi besieged Kaminoyama Castle south of Yamagata, held by the Mogami retainer Satomi Minbu; the Uesugi forces conquered it but suffered setbacks thanks to a