During this period, the clan was threatened from the north by Date Masamune and from the south by Hōjō Ujinao; however, because he quickly pledged allegiance to Toyotomi Hideyoshi during the Siege of Odawara (1590), he was able to retain his landholdings.

Under Hideyoshi's banner, he was counted among the six greatest generals of the Toyotomi clan, together with Tokugawa Ieyasu, Maeda Toshiie, Shimazu Yoshihiro, Mōri Terumoto, and Uesugi Kagekatsu.

During the siege of Odawara he was also able to extend his control to cover the over the whole of Hitachi Province (with the exception of the territory of the Yūki clan), by defeating various supporters of the Hōjō, so that by the end of the campaign his kokudaka was ranked at over 350,000 koku.

Instead of sending his army, he sent a small number of horsemen as reinforcements to Tokugawa Hidetada's attack on the Sanada clan, but for the most part remained in Mito attempting to stay neutral in the conflict.

After arriving at their new domain in 1603, the Satake immediately had to face a rebellion of local rōnin loyal to Onodera Yoshimichi, the former master of the region, which they defeated relatively quickly.

[3] Subsequently, Yoshinobu took steps to gain favor with the new Tokugawa government by actively participating in the Siege of Osaka, fighting Toyotomi commanders such as Kimura Shigenari and Gotō Matabei at the Battle of Imafuku.