sˈoʊmə mˈɔːɹətsjˌuːn wʌzðə jˈʌŋɡɚ sˈʌn ʌv tʃˈiːbə tsˈuːnɪtˌeɪn, ænd wɪð hɪz fˈɑːðɚ wʌzɐ sˈæmjʊɹɹˌaɪ ɪnðə sˈɜːvɪs ʌv mˌɪnɐmˈoʊɾoʊ nˈoʊ jˌoːɹɪtˈoʊmoʊ.
Sōma Morotsune was the younger son of Chiba Tsunetane, and with his father was a samurai in the service of Minamoto no Yoritomo.