In the 1561 siege of Odawara, a battle of Japan's Sengoku period, Uesugi Kenshin attacked Odawara castle. This was the first of several sieges which would befall Odawara castle, the home castle of the Hà Âjà  clan.
In 1559, Kenshin was pushed once again by Uesugi Norimasa to take control of the Kantà  back from the Hà Âjà Â, and in 1560 he was able to comply. In August of the same year, he put southern Echigo under control of a five-man council for broad mobilization, as well formed a small investigative council for any kind of unrest. In 1561 he marched to Odawara.
Fearing Hojo's expansion, various Kanto lords like the Satake and Satomi joined the Uesugi army, bringing its total strength to around 100,000.
Uesugi Kenshin was at the height of his campaign against the Hà Âjà  clan, as he captured several of their castles. Kenshin was successful in taking a number of castles from the Hojo clan, like Numata Castle and Umayabashi Castle.
Later, Kenshin besieged the Hà Âjà Â's main castle, Odawara Castle. The Uesugi breached the defenses, and burned the castle town. However, Kenshin would withdraw after two months. This came as the result of a lack of adequate supplies, and the reappearance of Takeda Shingen, Kenshin's long-time rival, who was threatening his territories.
The Odawara castle itself however remained unconquered; this ended the first of three sieges of the Odawara castle.