Washington Dec. 22. 08.
By the treaty of 1803, we obtained from the Kaskaskias the country as far as the ridge dividing the waters of the Kaskaskias, from those of the Illinois river. by the treaty of 1804, with the Sacs & Foxes they ceded to us from the Illinois to the Ouisconsin. between these two cessions is a gore of country, to wit, between the Illinois river & Kaskaskia line, which I understand to have belonged to the Piorias, & that that tribe is now extinct. if both these facts be true, we succeed to their title by our being proprietors paramount of the whole country. in this case it is interesting to settle our boundary with our next neighbors the Kickapoos. where their Western boundary is, I know not; but they cannot come lower down the Illinois river than the Illinois lake on which stood the old Pioria fort, & perhaps not so low. the Kickapoos are bounded to the S.E. I presume by the ridge between the waters of the Illinois & Wabash to which the Miamis claim; & N.E. by the Poutewatamies. of course it is with the Kickapoos alone we have to settle a boundary. I would therefore recommend to you to take measures for doing this. you will of course first endeavor with all possible caution to furnish yourself with the best evidence to be had of the real location of the S.W. boundary of the Kickapoos, and then endeavor to bring them to an acknolegement of it formally by a treaty of limits. if it be nothing more, the ordinary presents are all that will be necessary: but if they cede a part of their own country, then a price proportioned will be proper. in a letter to you of Feb. 27. 1803. I mentioned that I had heard there was still one Pioria man living, & that a compensation making him easy for life should be given him, & his conveyance of the country by a regular deed be obtained. if there be such a man living, I think this should still be done: the ascertaining the line between the Kickapoos & us is now of importance because it will close our possessions on the hither bank of the Misipi from the Ohio to the Ouisconsin, and give us a broad margin to prevent the British from approaching that river, on which, under color of their treaty, they would be glad to hover that they might smuggle themselves & their merchandize into Louisiana. their treaty can only operate on the country as long as it is Indian; and in proportion as it becomes ours exclusively, their ground is narrowed. it makes it easier too for us to adopt on this side of the Misipi a policy we are beginning on the other side, that of permitting no traders, either ours or theirs, to go to the Indian towns, but oblige them all to settle and be stationary at our factories, where we can have their conduct under our observation & controul. however our first object must be to blockade them from the Missipi: and to this I ask the favor of your attention, and salute you with great friendship & respect.
DLC: Papers of Thomas Jefferson.