So

Korean (Sŏ): although there are two Chinese characters for the Sŏ surname, one of these is extremely rare and can be discounted (there are only about two hundred people in Korea who use this rare character). Some records indicate that the more common character for Sŏ has as many as 165 clans, but only eleven of them can be documented. The first recorded ancestor of the Sŏ clans seems to be a Shilla figure named Sŏ Shin-il. According to some legends, the rulers of the Old Chosŏn kingdom (died 194 BC) were driven from power by the Wiman Chosŏn and settled in the Ich'ŏn area. The Sŏ clans are among the descendants of these ancient rulers. About fifty percent of modern members of the Sŏ clans live in the Kyŏngsang provinces or in Chŏlla South province.