From the Texas State Historical Association
United States renounces claims to Texas
On this day in 1819 the Adams-OnÃs Treaty was signed by President John Quincy Adams for the United States and LuÃs de OnÃs for Spain. The treaty renounced the United States claim to Texas.
It fixed the western boundary of the Louisiana Purchase as beginning at the mouth of the Sabine River and running along its south and west bank to the thirty-second parallel and thence directly north to the RÃo Roxo, or Red River, "then following the course of the RÃo Roxo westward to the degree of longitude 100 west from London and 23 from Washington; then, crossing the said Red River, and running thence, by a line due north, to the river Arkansas; thence, following the course of the southern bank of the Arkansas to its source, in latitude 42 north; and thence by that parallel of latitude to the South Sea. The whole being as laid down in Melish's map of the United States."
Spain delayed ratification of the Adams-OnÃs Treaty until 1821. By that time Mexico had declared her independence of Spain and refused to recognize the treaty boundary line.
Craig