Madam Yoko or Mammy Yoko (ca. 1849–1906) was a leader of the Mende people in Sierra Leone. Combining advantageous lineage, shrewd marriage choices and the power afforded her from the secret Sande society, Yoko became a leader of considerable influence. She expanded the Mende Kingdom and at the time of her death, she was the ruler of the vast Kpa Mende Confederacy.
Madam Yoko, originally called Soma, was born around 1849 in the Gbo Chiefdom. She changed her name to Yoko at her Sande initiation ceremony, during which time she became known for her graceful dancing. Yoko's first marriage, which was unsuccessful, was to a man named Gongoima. After leaving Gongoima, Yoko's second husband was Gbenjei, Chief of Taiama. Although Yoko remained childless, Gbenjei made her his great wife, giving her economic power within her household.
Following Gbenjei's death, Yoko married Gbanya Lango. In 1875, Gbanya was detained by British colonial officials in Taiamawaro. Yoko went directly to Governor Rowe to appeal for her husband's release. Rowe was impressed with Yoko's appeal and Gbanya was flogged, and then released. Following this incident, Gbanya made Yoko his great wife and began sending her on diplomatic missions. With the Sande, Yoko was able to wield significant power, not only amongst women, but Mende society as a whole. As a leader in this women's secret society, she made political alliances and took younger initiates as "wards" — later marrying them into other aristocratic lineages in an imitation of the trajectory of her own rise to power. In 1878, following her third husband's death, Yoko became the chief of Senehun. By 1884 she was officially recognised as "Queen of Senehun". This recognition came not only from her own people, but also from the British. She died in 1906, rumoured to have committed suicide. Having no descendants of her own, she was succeeded by her brother Lamboi.
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