After occupying Nagaoka-jo Castle, Kuroda made a plan to threaten the enemy from behind by advancing to Niigata via a sea route and thereby cut the supply of arms and ammunition to the enemy, and he landed at Matsugasaki leaving the main government force with Yamagata.
長岡城を占領したとき、黒田は海路新潟に出て敵の背後を脅かし、武器弾薬の補給を断つ作戦を立て、山縣に官軍主力を預けて自らは松ヶ崎に上陸した。