Toshiie served Oda Nobunaga from childhood (first as a page) and his loyalty was rewarded by being allowed to be the head of the Maeda clan, very unusual for a fourth son with no apparent failures among his elder brothers.

Just as Hideyoshi was known as Saru, 猴 or "monkey," it is believed that Toshiie was called Inu, 犬 or "dog" by Nobunaga.

Due to a long-standing belief that dogs and monkeys are never friendly to each other, Toshiie is often depicted as reserved and stern, in contrast to Hideyoshi's talkative and easy-going nature.

Toshiie began his career as a member of the akahoro-shū (赤母衣衆), the unit under Oda Nobunaga's personal command.

During his military career, Toshiie made the acquaintance of many important figures, such as Hashiba Hideyoshi,[1] Sassa Narimasa, Niwa Nagahide, Ikeda Tsuneoki, and others.

After defeating the Asakura clan, Maeda fought under Shibata Katsuie in the Hokuriku area.

In 1584, after Shibata's defeat, Toshiie become leading general for Hideyoshi in Komaki Nagakute Campaign and was forced to fight another of his friends, Sassa Narimasa at the Battle of Suemori Castle.

In 1591, he helped suppress the Kunohe rebellion in many locations along with Tokugawa Ieyasu and many generals from northern Japan.

Ishida Mitsunari and other magistrates relied on Toshiie, and tensions between the Tokugawa and Maeda clans reached a critical point.

Many influential daimyo, including Mōri Terumoto, Uesugi Kagekatsu, Ukita Hideie, Katō Kiyomasa, and Hosokawa Tadaoki, supported Toshiie.

[6] Before dying in 1598, Hideyoshi named Toshiie to the council of Five Elders to support Toyotomi Hideyori until he was old enough to take control on his own.

Intense debates took place, but ultimately, Toshinaga's mother, Matsu, persuaded everyone by saying, "For a samurai family, preserving the household is paramount.

Strong-willed from childhood, she was well-versed in the martial arts and was instrumental in Toshiie's rise to success.

After her husband died, Matsu, then known by her Buddhist nun name of Hoshun-in, assured the safety of the Maeda clan after the year 1600 by voluntarily going as a hostage to Edo, capital of the new shōgun, Tokugawa Ieyasu, whom she loathed throughout her life as she watched him, her husband, and Hideyoshi compete for power.