|State of Tan|
|Languages||Various Chinese languages|
Tan (Chinese: 譚國; pinyin: Tán; Wade–Giles: Tan2; 1046–684 BCE) was an ancient state located in present-day Shandong Province, China. It is the first state reported to be "extinguished"  during the Spring and Autumn period.
In 1046 BCE, Zhou, the last king of the Shang Dynasty, was defeated at the Battle of Muye by King Wu, founder of the Zhou Dynasty. Following this victory, he founded a number of small subordinate vassal states  to be ruled by his brothers and generals. One of these was the State of Tan, which was located just east of present-day Jinan, the capital of the present-day Shandong Province. The Tan rulers, who were reputed to be descendants of Yu the Great (the legendary ancient king and founder of the Xia Dynasty), were given the then-new heredity title of zijue (tzu-chueh (子爵), viscount).
In February 684 BCE, when rulers of neighboring states went to congratulate Duke Huan of Qi, ruler of the neighboring State of Qi, on defeating the State of Lu and the State of Song, Xian Li, the ruler of Tan did not go.
In October later that year, the Qi ruler used this discourtesy as an excuse to attack Xian Li and his three brothers. After ten days, his siege was successful, and the Tan ruler fled with 200 members of the royal family to the State of Ju, where his son, Qi Yi (祁義), was the ruler. Qi Yi was the first to change his clan name to Tan in memory of defeated state.
Today, Tancheng claims to be the ancient capital of this State of Tan. However, it has also been argued that it is actually the capital of a State of Tan established during the Tang Dynasty. Others argue that the ancient capital is the present-day Mingshui Sub-district of the city of Zhangqiu in Shandong Province.
- The term implies the destruction of its Ruling House, the abolition of its sacrifices, and the absorption of the people and territory by the prevailing Power.
- Zuo Zhuan, Duke Zhuan 莊, 10th year 
- The traditional date for the Battle of Muye was 1122 BCE.
- It is estimated that there were some 170 vassal states established during the reign of the Zhou dynasty.
- Tan Genealogy: Heritage and Lineage by Henry Tom, privately published, Frederick (MD) 2009.
- In Search of Your Asian Roots: Genealogical Research on Chinese Surnames by Sheau-yueh J Chao, published by Clearfield Co, Baltimore 2000.