Sunheung An clan

The Sunheung An clan (순흥 안씨, ) is a clan connected with the town of Sunheung, South Korea, and was well-known during Goryeo Dynasty and early Chosun Dynasty for its 'blue-blood' status. An is also spelled as Ahn in its romanized version, but there is no difference in the two romanized versions apart from the spellings.
73.5% of people with the Korean surname 'Ahn' belong to the Sunheung An clan. The 2000 South Korean census counted 468,827 members of the "Sunheung" Ahn clan. It is a native clan connected with the town of Sunheung, Korea. 
Sunheung Clan in Koryeo Dynasty.
They have enjoyed "blue-blood" status as nobility (Yang-Ban) since their earliest history in the Goryeo Dynasty and throughout the Chosun Dynasty (July 1392 - August 1910). The founder of the Sunheung Ahn was a famous military commander of Koryeo named Ahn Ja-mi. Ahn Ja-mi commanded Hongwiwi, the troop that escorted the Royal family, greeted foreign envoys, participated national ceremonies, fought in wars, and guarded the frontier(border are) in Goryeo Dynasty. Ahn Jami was honoured with the title of the supreme commander of Samhowi(one of 3 Central Command) by King Sinjong of Koryeo. Founder Ahn Jami had three sons, Ahn Yeong-yu, Ahn Yeong-rin, Ahn Yeong-hwa. Sunheung-Ahn Clan is divided into 3 different branches based on which of the three sons they descend from. The First Branch descending from Ahn Yeong-yu is called Lord (Duke) Chumil Branch (1파 추밀공파(樞密公派)). The Second Branch descending from Afhn Yeong-rin is called Lord (Duke) ByeolJang Branch (2파 별장공파(別將公派)). The Third Branch descending from Ahn Yeong-hwa is called Lord (Duke) Kyoseo Branch (3파 교서공파(校書公派)). From these three branches, there are 14 more sub-branches from the First Branch, 4 more sub-branches from the Second Branch, and 4 more sub-branches from the Third Branch.
Sunheung-Ahn Clan became one of the most powerful and famous noble clans after Ahn Hyang, who is grandson of Ahn Yeong-yu (the founder of the Lord (Duke) Chumil Branch and the great-grandson of Ahn Jami, the founder of the Sunheung-Ahn Clan. An Hyang passed the Gwageo(State examination) in 1260(Wonjong 1). And he served as Docheomuijungchan(Vice-premier). An Hyang is considered the founder of Neo-Confucianism in Korea, introducing Song Confucianism to the Koryeo Empire. An Hyang is generally numbered among the clan's most illustrious members, and founded a branch of his own within Sunheung-Ahn Clan, called Lord (Duke) Moonsun Sub-Branch (문성공파(文成公派)). Subsequent to An Hyang and for the rest of Koryeo Dyasty, Sunheung-Ahn Clan had members passing the Gwageo(State Examination) for 11 generations, 20 members of the Clan were made into Dukes or Grand Dukes (봉군(封君)), and produced 17 Daejehaks(대제학), which were then the highest office academics could reach in the Royal Court, equivalent to today's Ministers of Education.
Sunheung Clan in Chosun Dynasty.
After the fall of Koryeo Dynasty and the establishment of Chosun Dynasty in 1392, Sunheung-Ahn Clan still remained one of the most powerful and famous noble clans, and was known for being one of the Six Greatest Clans in the kingdom. During Chosun Dynasty, 641 members of Sunheung-Ahn Clan passed the Gwageo(State Examination).
However, the Sunheung-Ahn Clan lost its power in mid 15th Century due to its support of King Danjong, a young King who was overthrown and then later assassinated by his uncle in the midst of political turmoil. The Sunheung-Ahn Clan then led the movement to restore King Danjong back to the throne, which is one of the well-known tragedies in the history if Chosun Dynasty. Once the movement failed, Sunheung-Ahn clan lost its status of one of the most prestigious clans in the kingdom, and members of the clan left the ancestral home of Sunheung and scattered around the kingdom to run away the oppression of the government. The famous PiKkeut Village (End of the Blood Village, 피끝마을) resulted from the failure of this movement. The village gained its name from massacre committed by the Chosun Dynasty on the 700 inhabitants of Sunheung, the ancestral home of Sunheung-Ahn Clan, after the failure of the movement. The blood of the massacred people flowed in the stream and then ended in the PiKkeut Village, and thus the village got its name. The tragedy of Sunheung and PiKkeut Village was romanticised as the tragic fate of the Sunheung-Ahn Clan that stayed loyal to the young king, such as in DanJongEhSa (단종애사, 端宗哀史), a popular early 20th century Korean novel that described the life of King Danjong. Due to Sunheung-Ahn clan's famous history of staying loyal to King Danjong, surname Ahn became synonymous to stubborn and loyal. There are three Korean surnames often associated with being stubborn-Ahn, Kang, and Choi-and among the three surnames Ahn is most famous due to this tragic history.
As the consequence of the failure of Danjong Restoration Movement, Sunheung-Ahn Clan were charged with treason. The ancestral home of Sunheung was called the Land of Treason, and the clan could not regain its former power and glory for the rest of the Chosun Dynasty. Due to this the Clan did not produce many famous figures for the rest of Chosun Dynasty. However, the Clan produced many well-known members after the fall of Chosun Dynasty in late 19th century.
Famous Members of Sunheung Clan.
Most influential and respected members of the Sunheung Clan are An Hyang, who is considered the founder of Neo-Confucianism in Korea during Koryeo Empire, and An Chang Ho (Title: Dosan), a political leader during Colonial Japan and the founding of the democratic government of Korea, whose life ended shortly after the arrest and release by the Colonial Japanese Government.