PINCKNEY'S TREATY of 1795, also known as the Treaty of San Lorenzo, between the United States and the Spanish Empire, established the thirty-first parallel as the border between the United States and Spanish West Florida. Spain had ceded that area in 1763 to Great Britain, which had moved the boundary from the thirty-first parallel to a line north of the thirty-second parallel. When the British gave Florida back to Spain after the War of Independence, this boundary was disputed. In addition to meeting the American position on this issue, Spain allowed the United States free navigation of the Mississippi River to the Gulf of Mexico and granted it the right to deposit goods in New Orleans. This was of vital importance to the farmers and merchants who lived in Kentucky and Tennessee and to the settlers of the Ohio Valley, who now could ship their harvests and goods on the waterways to the eastern seaboard of the United States, to Europe, or to other areas. Additionally, both nations agreed not to incite attacks by Native Americans against the other
nation. Signed at San Lorenzo El Real on 27 October 1795, the "Treaty of Friendship, Limits, and Navigation Between Spain and the United States" was negotiated by Thomas Pinckney, minister to Great Britain, who had been sent to Spain as envoy extraordinaire.
See also Spain, Relations with .