Swahili or Kiswahili (known in Swahili itself as Kiswahili) is a Bantu language spoken by various ethnic groups that inhabit several large stretches of the Mozambique Channel coastline from northern Kenya to northern Mozambique, including the Comoro Islands. It is also spoken by ethnic minority groups in Somalia. Although only five million people speak Swahili as their mother tongue, it is used as a lingua franca in much of East Africa, meaning the total number of speakers exceeds 60 million. Swahili serves as a national, or official language, of five nations: Tanzania, Kenya, Uganda, the Comoros and the Democratic Republic of the Congo.

Some Swahili vocabulary is derived from Arabic through more than twelve centuries of contact with Arabic-speaking inhabitants of the coast of southeastern Africa. It has also incorporated Persian, German, Portuguese, English, and French words into its vocabulary through contact during the past five centuries.

Scholars lack sufficient historical or archaeological evidence to allow them to state exactly when and where either the Swahili language or the Swahili culture emerged. Nevertheless, it is assumed that the Swahili speaking people have occupied their present territories, hugging the Indian Ocean, since well before 1000 CE. Arab traders are known to have had extensive contact with the coastal peoples from at least the 6th century CE, and Islam began to spread along the East African Coast from at least the 9th century.

Song In (in hangul 송인, in hanja 宋仁) was a civil official in the mid-Goryeo era who became the intermediary founder of the Jincheon Song clan. His highest post was munha pyeongjangsa (문하 평장사). This was the highest government position in the period. Song In was responsible for administration, judicial affairs and economy in the district.

As he performed meritorious deeds during the King, he was conferred with Chanhwagongsin and Jincheonbaek. Baek was a position of politicians who were responsible for administration, judicial affairs and economy in the district. As the government created him Jincheonbaek, his family started regarding Jincheon as their origin. Hence, the family origin became Jincheon Song.

When he was in the position of Sangsanbaek, he tried to be just and fair in all the administrative affairs and strived to enhance the welfare of his people. He also focused on education for the youth and courtesy for people, which made his district famous for most excellent behaviors in the nation. After that, the people have long paid tribute to his feats.