After the Battle of Sekigahara, Naomasa II, one of Tokugawa-shitenno (four generals serving Tokugawa Ieyasu, was given the land in northeastern part of Omi Province with 180 thousand goku crop yields by his distinguished military service, and entered Sawayama-jo Castle that had belonged to Mitsunari ISHIDA, his enemy and the commander of West camp.
徳川四天王の一人・井伊直政は、関ヶ原の戦いの後、その軍功により18万石にて近江国北東部に封ぜられ、西軍指揮官・石田三成の居城であった佐和山城に入城した。