Bryan v. Kennett, 113 U.S. 179 (1885), was a United States Supreme Court case in which the Court held that, under the treaty providing for the Louisiana Purchase, the United States would recognize property interests granted by the previous sovereign governments prior to the Purchase, even if the grant had been inchoate or incomplete.

[2] However, the Court had already discussed and confirmed the legality of the Louisiana Purchase much earlier in American Insurance Co. v. Canter, 1 Peters (26 U.S.) 511 (1828).

He relocated to upper Spanish Louisiana, an area then controlled by Spain (which later became the U.S. state of Missouri), due to rich lead deposits in the region.

[1][5] In 1835, Deane brought a quiet title action in equity in Missouri against the heirs of James Bryan, who by then were living in Texas and failed to appear.

Bryan's heirs now brought an action for ejectment of Deane's successors in title, alleging (among other things) that Austin had not received complete title to his land from the Spanish government and thus he could not have mortgaged the land, which reverted to the possession of the United States and then passed to Bryan's heirs by operation of the Act of Congress.

In so holding, the Court reaffirmed its position, as set forth in previous cases, that "in that treaty by which Louisiana was acquired, the United States stipulated that the inhabitants of the ceded territory should be protected in the free enjoyment of their property; that the term 'property,' as applied to lands comprehends every species of title, inchoate or complete, and embraces rights which lie in contract, executory as well as executed, and that in this respect the relation of the inhabitants to their government was not changed, the new government taking the place of that which had passed away."

In making this ruling on the property issue, the Court cited its previous opinions in Strother v. Lucas, 31 U.S. 763 (1832), Soulard v. United States, 29 U.S. 511 (1830), and Landes v. Brant, 51 U.S. 348 (1850) in support.

In order to quiet the fears of those 'who have been in possession for half a century, claiming the land adversely against everybody, as well as the United States,' the act of 1874 was passed.