This case is brought before this court by an appeal from the decree of the district court for the eastern district of Louisiana.

Under a practice which is peculiar to Louisiana, the attorney of the United States, on their behalf, presented a petition to the court; which represented that the mayor of the city of New Orleans, in pursuance of an ordinance of the city council, had advertised for sale, for a day then past, and was about to advertise anew, for sale, in lots, the vacant land included between Ursuline Levee and Garrison streets, and the public road in the city of New Orleans; and also, the vacant land included between Customhouse Levee and Bienville street, and the public road in the said city.

New Orleans v. United States (35 U.S. 662)/Opinion of the Court

And the petitioner further stated, that by the treaty of cession of the late province of Louisiana by the French republic to the United States of America, the United States succeeded to all the antecedent rights of France and Spain, as they then were, in and over the said province; the dominion and possession thereof, including all lands which were not private property; and that the dominion and possession of the said vacant lands, ever since the discovery and occupation of the said province by France, remained vested in the sovereign; and had not, at any time prior to the date of said treaty, been granted by the sovereign to the city. And the petitioner prayed for an injunction to restrain the city council from selling the land, or doing any other act which shall invade the rightful dominion of the United States over said land, or their possession of it; and a perpetual injunction was prayed.

New Orleans v. United States (35 U.S. 662)/Opinion of the Court

To this petition the mayor, aldermen and inhabitants of the city answered, and denied the material facts and allegations in the petition; and they specially denied that the dominion and possession of the land, at the time Louisiana was ceded to the United States, were vested in either the king of Spain or the sovereign of France, either as vacant land or under any other denomination.

New Orleans v. United States (35 U.S. 662)/Opinion of the Court

And in a supplemental answer the respondents say, that the inhabitants of the city of New Orleans are the true and lawful proprietors of the vacant lots they have been enjoined not to sell.

1. 'Because all the space of ground which exists between the front line of the houses of the city and the river Mississippi was left by the king of France, under the name of quays, for the use and benefit of the inhabitants of the city.

2. 'Because if since the foundation of the city of New Orleans said space of ground became wider than was necessary for the public use, and the quays of the city, it was in consequence of an increase formed by alluvion in the greatest part of the front of the city; and the works which were necessarily made from time immemorial by the inhabitants of the city, or at their expense, to the levee in front thereof, to advance it nearer to the river than it was formerly.

3. 'Because, by the laws of Spain which were in force at the time when said alluvions were formed, and said works were made, alluvions formed by rivers in front of cities belonged to the inhabitants thereof; who may dispose of the same as they think it convenient, on their leaving what is necessary to the public use.'

And the respondents say, that the vacant lots are of great value; and cannot be disposed of unless they shall be indemnified by the government, &c.

A general replication was filed by the district attorney in behalf of the United States.

Statements of facts signed by the parties appear in the record.

If this cause be considered on the broad ground on which it is presented by the facts and the arguments of counsel, it is one of great importance. In one view, the title to property of the value of several millions of dollars, depends upon its decision; and in any aspect in which it may be considered, principles of the civil law, and the usages and customs of the governments of France and Spain, and also, it is insisted, important principles of the common law, as well as the effect of certain acts of our own government, are involved.

In the able arguments which have been heard at the bar, these topics have been elaborately examined and variously illustrated; and it now becomes the duty of the court to pronounce their opinion in the case. Being constituted the organ of that opinion, the matters in controversy will be considered under the following arrangement.

1. The rights of the plaintiffs in error, by the principles of the common law.

2. Their rights under the laws and usages of France and Spain.

3. The interest of the United States in the property claimed by the city, and their jurisdiction over it.