Through the 1820s and the turn of the decade, American settlers continued pressuring the US government to remove the Seminole from Florida to make way for their desired agricultural development. In 1832, a few Seminole chiefs signed the Treaty of Payne's Landing, by which they agreed to give up their Florida lands in exchange for lands west of the Mississippi River in Indian Territory. According to legend, Osceola stabbed the treaty with his knife, although there are no contemporary reports of this. Donald L. Fixico, an American Indian historian, says he made a research trip to the National Archives to see the original Treaty of Fort Gibson (also known as the Treaty of Payne's Landing), and that upon close inspection, he observed that it had "a small triangular hole shaped like the point of a knife blade".