Matȟó Wayúhi ("Conquering Bear") (c. 1800 – August 19, 1854) was a Brulé Lakota chief who signed the Fort Laramie Treaty (1851).
He was killed in 1854 when troops from Fort Laramie entered his encampment to arrest a Sioux who had shot a cow belonging to a Mormon emigrant.
Given the encroachment of white settlers with their wagon trains and disease, the Native Americans feared the loss of their way of life and culture.
In August, 1854, Conquering Bear and his people were encamped near Fort Laramie in a state of strained peace, adhering to the treaties as they understood them.
Supplies and food were to be delivered, as per the treaty agreement, and many different bands of the Sioux had gathered together for this purpose along the North Platte River.
It is estimated that some 600 lodges made up the encampment, making a total population of some 4,000 people, 1,200 of which were warriors or of fighting age.
Lt. Fleming was swayed by the migrating Mormons, and his second in command, Second Lieutenant John Lawrence Grattan, was eager to take a detachment to arrest High Forehead.
Trader James Bordeau, who owned a nearby trading post, was in the encampment at the time, and later relayed the most reliable accounts of what transpired.
Bordeau stated that Auguste had taunted the Sioux warriors, calling them women, and was openly boasting that the soldiers would kill them all.