Horio Tadauji

{{family name hatnote|Horio|lang=Japanese}}

File:Horio Tadauji.jpg

Horio Tadauji (堀尾 忠氏; 1578 – August 8, 1604)

was a tozama daimyō in the Azuchi–Momoyama and Edo period.

His father was Horio Yoshiharu.{{Cite journal |last=青翔 |first=吉山 |date=2020 |title=遠藤利貞：上野戦争（1868年）の敗走兵から「学」としての「日本数学史」の創始者への足跡 |url=https://www.jstage.jst.go.jp/article/jyu/32/2/32_269/_article/-char/ja/ |journal=四日市大学論集 |volume=32 |issue=2 |pages=269–278 |doi=10.24584/jyu.32.2_269}}

He was the second leader of the Matsue clan.

In 1600 at the Battle of Sekigahara, acting as a substitute for Yoshiharu who had been injured in the run up to the battle, Tadauji took part in Tokugawa Ieyasu's force.{{Cite book |last=Glenn |first=Chris |url=https://books.google.com/books?id=QrNFEAAAQBAJ&dq=%22Horio+Tadauji%22&pg=PP1 |title=The Battle of Sekigahara: The Greatest, Bloodiest, Most Decisive Samurai Battle Ever |date=2021-12-31 |publisher=Frontline Books |isbn=978-1-3990-1416-8 |language=en}}

After the battle, Ieyasu praise Tadauji for his credit and add his domain to 240,000 koku at Izumo Province.

In 1604, Tadauji died before his father Horio Yoshiharu, Tadauji died young from a disease, and his son, Horio Tadaharu succeeded to head of a house. Tadaharu was so young (9 years old), later Yoshiharu ruled as a godfather until his own death on 1611.