During the 1840s and 1850s the Métis followed the buffalo herds further into the Dakota Territory bringing them into conflict with the Sioux. Cuthbert Grant, an early captain of the buffalo hunt, negotiated a treaty in 1844. Another treaty was concluded in 1851 and another in 1854 but Métis hunting groups were still being attacked by the Sioux. Jean Baptiste Wilkie, the leader of the 1840, 1848 and the 1853 summer hunt, helped negotiate a peace treaty in 1859 and another in 1861 between the Métis, Chippewa and the Sioux (Dakota) to set hunting boundary lines. These peace overtures did not last and conflict continued between the Métis and the various Sioux groups even after the Dakota War of 1862.