Taean used to be called “Sotaehyeon” during the Three Kingdoms Period until the name, “Taean,” was given in 1298 (24th year of King Chungnyeol’s reign over Goryeo). It was promoted to the status of “gun” in 1895 in the Joseon Dynasty, and it was incorporated into Seosan-gun, along with Haemi-gun, in 1914.

In 1298 (24th year of King Chungnyeol’s reign over Goryeo), “Sotaehyeon” was renamed “Taean.” Then, it was later promoted to the status of “gun.”

April 1, 1914: Taean-gun was incorporated into Seosan-gun and demoted to the status of “myeon” during the Japanese occupation period.

1972: Anmyeon-myeon Gonam Office was established.

July 1, 1973: Taean-myeon was promoted to Taean-eup pursuant to Presidential Decree No. 6542.

July 1, 1973: Pursuant to Presidential Decree No. 6542, Cheongsan-ri and Masan-ri of Ibuk-myeon were incorporated into Wonbuk-myeon, and Ganwoldo Island of Anmyeon-myeon into Buseok-myeon.

Dec. 1, 1980: In accordance with Presidential Decree No. 10050, Anmyeon-myeon was promoted to Anmyeon-eup.

Jan. 10, 1983: Pursuant to Presidential Decree No. 11075, parts of Sapsido-ri, Ocheon-myeon, Boryeong-gun (Naepasudo, Oepasudo and Oedo islands) were incorporated into Anmyeon-eup.

May 7, 1984: In accordance with Article 10 of the Enforcement Decree of the Local Autonomy Act, the Seosan-gun Seobu Office was established.

April 1, 1986: Pursuant to Presidential Decree No. 11874, Anmyeon-eup Gonam Office was promoted to Gonam-myeon.

Jan 1, 1987: In accordance with Act No. 12001, Ibuk-myeon was renamed as Iwon-myeon.

Jan 1, 1989: In accordance with Act No. 4050, Taean-gun (2 eups and 6 myeons) was separated from Seosan-gun.