Following the death of Nobunaga at Honno-ji in 1582, many of his generals raced to confront the traitor, Akechi Mitsuhide. Thirteen days later at Yamazaki, Hideyoshi vanquished Akechi. Nobunaga had three sons that left, Hidekatsu, Nobuo, and Nobutaka. The decision of who was to take over control of the Oda clan was debated between Nobunaga's generals. It was decided that Nobutaka's son, Samboshi, would take over and his father and uncle would serve as guardians. However, they were soon disputing.

Shibata and Hideyoshi grew concerned about each other's motives. On one side was Shibata Katsuie who supported Nobutaka and on the other was Hideyoshi who supported Nobuo. It became apparent to Shibata and the other generals that Hideyoshi intended to use his new found fame to manipulate the heir and take the throne by default.

Hideyoshi soon found himself at war with his former comrades. His position was grave and he was surrounded by three enemies: Nobutaka in Gifu, Takigawa Kasumasa in Kameyama, and Shibata in the north. All of Hideyoshi's routes to the capital, save the west, were obstructed by these three.

Hideyoshi invited Nobutaka and Kazumasa to peace talks, but the two ignored him. Knowing that Shibata was unable to come to Nobutaka's aid because of snow, Hideyoshi attacked Nobutaka at Gifu and soon knocked him out of the contest. Later in Kyoto, Hideyoshi was informed that Takigawa and Shibata's son, Kazutoyo, were planning to move against him. Hideyoshi secured Kazutoyo's castle in Nagahama through a bribe and then moved on to Kameyama and forced Takigawa's surrender. Knowing that Shibata Katsuie would advance when the snow thawed, Hideyoshi ordered the construction of several fortresses around Shizugatake to guard his frontier.

In March 1583 Nobutaka revolted in Gifu and troops were sent to quell him. Shibata, had meanwhile relocated his base to Uchinakao-yama, north of lake Yogo. He was determined to have a showdown. Hideyoshi, meanwhile, relocated his base to Kinomoto and made ready to march north up the Hokkoku-kaido.

On 4 April Yamaji Masakuni, who was commander of Shinmei-san, was transferred to Dougi-san because Hideyoshi suspected him of secretly communicating with Shibata. That same day Shibata threatened the fort, but soon withdrew. The next day Shibata attacked Touno-san, but was driven off by the counterattack of Hori Hidemasa.

As Hideyoshi had suspected, Yamaji was a traitor. On the 13^th he escaped from his troops and went to Sakuma Morimasa, Shibata's nephew, and informed him about the lack of defense at the forts Iwasaki-yama and Ooiwa-yama. On the 19^th Sakuma went to see Shibata Katsuie with the information. He persuaded Shibata to allow him to attack, but on the condition that he would withdraw after defeating the enemy. Shibata would march down the Hokkoku-kaido in support.

On 20 April at 2 a.m. the plan went into action. Sakuma Morimasa and Shibata's brother, Katsumasa, at the head of 10,800 troops, began their long march to the forts. At the same time Shibata Katsuie with 7,000 troops moved south along the Hokkoku-kaido. Meanwhile, Maeda Toshiie and his son Toshinaga encamped with 2,000 troops near Shinmei-san. There job was to prevent any relief effort by the defenders of Fort Shinmei. A detachment of 3,000 under Katsumasa left the main body to take up position to threat Shizugatake. The rest of the main body continued to march along the coast of lake Yogo.

At dawn all hell broke loose. Sakuma began an all-out attack on Ooiwa-yama, which, despite the loss of its commander, Nakagawa Kiyohide, held out for several hours. At Iwasaki-yama, Takayama Shigetomo fled to Kinomoto. Meanwhile, Katsumasa attacked Shizugatake. The garrison commander, Kuwayama Shigeharu, planned to evacuate, but reinforcements from Niwa Nagahide, who had come up by boat, changed his mind. Sakuma refused to retreat as per the agreement between he and Shibata.

At 2 p.m. Hideyoshi received word about the forts. The news sped Hideyoshi into action and he soon marched north. The journey from Ogaki to Kinomoto was 52 km, but the march was done with amazing speed and his forces arrived at 9 p.m.. Sakuma realized that the enemy was fast approaching, but calculated that it would take three days for the force to arrive; by that time the fort would fall. However, he was wrong, Hideyoshi was encamped only a day away. Hideyoshi's troops soon appeared in front of the enemy. At 11 p.m. Sakuma ordered his men to a defensive position at Gongen-zaka.

Knowing of Sakuma's retreat, Hideyoshi ordered an all-out attack at 2 a.m. on the 21^st. At 3 a.m. the first of Katsumasa's rearguards was attacked. The Battle of Shizugatake had begun.

In the north, Sakuma Katsuie moved his troops down the Hokkoku-kaido. At around 6 a.m. they were attacked by Hori Hidemasa, Hashiba Hidenaga, and Ogawa Suketada in the pass below Touno-yama. Shibata's advance was checked and his men were in retreat. Meanwhile, the troops of Sakuma and Shibata had stopped their retreat and formed a line around Gongen-zaka.

At 8 a.m., the troops of Kato Kiyomasa smashed into Sakuma's men near Gongen-zaka; the battle moving back and forth, up and down the slopes and around lake Yogo. Numerous bodies piled up along the slopes and lake Yogo was colored red with blood. Generals Haigo, Yamaji, and Katsumasa were killed. Sakuma tried to counterattack, but in his rear Maeda Toshiie, Kanamori Nagachika, and Fuwa Katsumitsu vacated their positions and moved towards Shiozu (it is said that they communicated with Hideyoshi before the battle). This treachery allowed Hideyoshi's troops at Shinmei-san and Dougi-san to attack the enemy flank. Sakuma's troops, now being assailed from the front and side, collapsed. Seven Hideyoshi samurai distinguished themselves in the battle and became known as the 'Seven Spears': Fukushima Masanori, Kato Yoshiaki, Wakizaka Yasaharu, Hirano Nagayasyu, Katagiri Katsumoto, Kasuya Takenori, and Kato Kiyomasa. The retreat soon turned into a rout and the winners pursed the enemy through the forests and thicket which littered the hillsides.

Meanwhile, watching the battle from Shizugatake, Hideyoshi moved his hatamoto to Syufukuji-zaka where he watched the rest of his forces encircle Sakuma. With the battle won around noon., he headed for Kitsune-zaka, where Katsuie was. By this time Katsuie had fought several times against Hori, Ogawa, and Hidenaga, and his forces had shrank to 3,000. Katsuie was all for fighting to the end, but was dissuaded by his vassal, Menju Katsuteru. He turned and fled north to his castle. The combined Hideyoshi force, in hot pursuit, moved up the Hokkoku-kaido and laid siege to Katsuie's fortress at Kita-no-sho.

Within hours the castle was in flames; Shibata committed seppuku. Nobutaka later committed suicide leaving only one son of Nobunaga's left, Nobuo, who decided to ally himself to the Tokugawa for protection. The battle had placed Hideyoshi in complete control of Nobunaga's domains. Only the Tokugawa were left to challenge him and that clash would come a year later in 1584 at Komaki.