Since 2008, the 100 Horses Society has been a community based organization that was established as the supporting Society for hosting the Lakota Coming of Age ceremony. The mission of 100 Horses Society is perpetually to ensure the continuance of the Isnati Ca Lowanpi Ceremony (Becoming a Woman Ceremony) for the next seven generations of young Lakota women on the Cheyenne River Sioux Tribe Reservation.  This is one of the seven ceremonies brought to the Lakota people from the White Buffalo Calf Woman.  It recognizes that a girl has become a woman and is now ready to take her place in the Lakota society.
For sixteen years the Society has hosted the ceremony, and 101 women have become Society members.  Both Grandmothers who started the 100 Horses Society are now over 75 years old and they have stood fast on the purpose of the Society as being established to insure that the ceremony would be available to women.  In 2019 the two Grandmothers “retired” from their posts and gifted that responsibility to younger women.  The Grandmothers continue to be mentors in the Society; however, the organization and administration now lies with these new leaders.  In this “changing of the guard” for the Society, the younger women have decided to expand the purpose of the 100 Horses Society. 

In April 2022, the leadership of the Society filed for non-profit status, thus creating The 100 Horses Women's Society, Inc.. The non-profit will aid us in our grassroots movement to "Empower the Matrilineal Leadership" within our Cheyenne River Sioux Tribe Reservation communities.