Takeo is located in the western part of Saga Prefecture. It is approximately 28 kilometers (17 mi) west of Saga City and approximately 30 kilometers (19 mi) east of Sasebo. Takeo has a complex topography including mountains, mountain basins and riverside plains.
Mountains: Mt. Mifune (210 m), Mt. Hachiman (764 m), Mt. Bi (518 m), Mt. Jinroku (447 m)
Rivers: Rokkaku River, Shiomi River, Yamanaka River
1889-04-01 - The modern municipal system was established. The current city region is occupied by 1 town (Takeo) and 11 villages (Asahi, Hashishita, Higashikawanobori, Kitagata, Kitsu, Nakato, Nishikawanobori, Sumiyoshi, Takeo, Takeuchi and Wakaki).
1900-06-07 - Takeo Village was incorporated into Takeo Town.
1944-04-29 - Kitamura Village became Kitamura Town.
1954-04-01 - Takeo Town absorbed the villages of Asahi, Hashishita, Higashikawanobori, Nishikawanobori, Takeuchi and Wakagi to create Takeo City. The villages of Sumiyoshi and Nakato were merged to create Yamauchi Village.
1956-04-01 - Hashishita Village was split and was incorporated into Kitagata and Shiroishi (respectively).
1960-09-01 - Yamauchi Village became Yamauchi Town.
2006-03-01 - The towns of Kitagata and Yamauchi were incorporated into Takeo City.