During the historical period of the Eastern Army led by Tokugawa Ieyasu against the Western Army led by Ishida Mitsunari, the position of Kato Kiyomasa and Fukushima Masanori was questioned, arguing that they seemed to have betrayed Toyotomi Hideyoshi and the Toyotomi family. However, is this really the case?If we do not only look at the following pattern of Japan's Sengoku period in which Kato Kiyomasa and Fukushima Masanori lived, but focus on the Battle of Sekigahara, we will find that these two are not traitors to the Toyotomi family, but can be said to be extremely loyal to Toyotomi Hideyoshi and the Toyotomi family.
Kiyomasa Kato and Masanori Fukushima, as representatives of the Arbitrari faction, had differences with the Bunji faction led by Ishida Mitsunari, but they did not join the Eastern Army led by Tokugawa Ieyasu for this reason alone. More importantly, their loyalty to the Toyotomi family. Although Tokugawa Ieyasu's later actions may have come as a surprise to them, their position was firm before the Battle of Sekigahara.
Before the Battle of Sekigahara, Tokugawa Ieyasu issued an order to the daimyo in the northeastern Kanto and Hokuriku regions under the name of "Naoe-like", and obtained funds and military rations from Toyotomi Hideyori to carry out the crusade against Uesugi Keikatsu. His actions were nominally legitimate military operations authorized by the Toyotomi regime to defeat the rebels. Ishida Mitsunari took the opportunity to attack Tokugawa Ieyasu in the rear, but all he got was a ** letter to Mitsushi, which seemed to have no legitimacy, and it was even less convincing for political opponents Kiyomasa Kato and Masanori Fukushima.
As a result, Kato Kiyomasa and Fukushima Masanori easily regarded Ishida Mitsunari as a traitor to the Toyotomi family and chose to join the Western Army led by Tokugawa Ieyasu against him. However, after the Battle of Sekigahara, Kiyomasa Kato and Masanori Fukushima also realized the reality that they were being used by Tokugawa Ieyasu, but it was too late, and the Toyotomi regime was already in jeopardy.
After Sekigahara, with the rise of Tokugawa Ieyasu's power, the contradiction between the arbitrary faction and the bunji faction could not be bridged. Although Tokugawa Ieyasu was able to reconcile, not only was he unwilling, but he also took the opportunity to weaken the Toyotomi family and exacerbate the contradictions between the two factions. Ishida Mitsunari saw clearly and knew that the Toyotomi family had no way out, and it was a good time for Tokugawa Ieyasu to lead his troops to defeat Uesugi Keikatsu.
Kiyomasa Kato and Masanori Fukushima showed loyalty to the Toyotomi family, and although they did not eventually fall with the Toyotomi family (Kato Kiyomasa died earlier than he had a chance), their loyalty to the Toyotomi family before Sekigahara was commendable. After the death of Maeda Toshiie, Tokugawa Ieyasu's power rose rapidly, and the contradictions between the arbitrary faction and the bunji faction could not be bridged. Of course, Tokugawa Ieyasu was able to reconcile, but not only was he unwilling, but he also took the opportunity to weaken the Toyotomi family and strengthen his own power through this civil strife.
Fukushima Masanori ended up with a tragic fate, also because he was too loyal to the Toyotomi family. Although Kiyomasa Kato and Masanori Fukushima recognized that they were being used by Tokugawa Ieyasu after the Battle of Sekigahara, the decline of the Toyotomi family was a foregone conclusion. Although they were unable to prevent the fall of the Toyotomi family, their loyalty to the Toyotomi family was still remarkable before Sekigahara. This history bears witness to the best support of the Toyotomi family by these two samurai on the premise of the survival of the family.