According to the Kikuyu myth of origin, a supernatural being known as Ngai, or Mwene Nyaga, who resides in Kĩrĩnyaga (Mt. Kenya), created the first man and woman, known as Gĩkũyũ and Mũmbi, respectively. The myth posits that one day Ngai gave Gĩkũyũ the fertile land between Mount Kenya (Kĩrĩnyaga), the Kĩrĩmambogo Hills (Kĩanjahĩ), the Ngong Hills (Kĩrĩmbirũ-irũ), and the Aberdare Ranges (Mĩtabũrũko ya Nyandarua). After inheriting the land, Gĩkũyũ and Mũmbi descended from the mountains and settled in Mũkũrwe wa Nyagathanga. The couple was blessed with nine daughters, namely Wanjirũ, Wambũi, Wanjikũ, Waceera (Njeri), Wangari, Wakĩũrũ (Nyambura), Wangechi (Waithĩra), Wairimũ, Wangũi (Waithiegeni), and Wamũyũ (Warigia/Wanjũgũ).
When the daughters were of marriage age, Gĩkũyũ sacrificed and prayed under a fig (mũgumo) tree, requesting Ngai to provide husbands to his daughters. The following day, nine men appeared under the Mũgumo and married his daughters, giving rise to the nine Kikuyu clans. The nine clans were named after each daughter and form the foundation of the Kikuyu heritage. These clans are Anjirũ, Ambũi, Anjikũ, Aceera, Angari, Akĩũrũ, Aithĩrandu, Agathigia, Angũi/Aithiegeni, and Aicakamũyũ.