Ludloff and Others v. United States was a Supreme Court case that dealt with the issue of whether the United States government had the right to take possession of land that had been granted to a private individual by the government of Mexico. The case arose when the United States government attempted to take possession of land that had been granted to a private individual by the government of Mexico prior to the Mexican-American War. The individual, Ludloff, argued that the United States had no right to take possession of the land as it had been granted to him by the Mexican government. The Supreme Court ultimately ruled in favor of the United States, finding that the United States had the right to take possession of the land as it had been acquired by the United States through the Treaty of Guadalupe Hidalgo, which ended the Mexican-American War. The Court held that the United States had the right to take possession of the land as it had been acquired through the treaty and that the Mexican government had no right to grant the land to a private individual. The Court also held that the United States had the right to take possession of the land as it was necessary for the public good.

In the case of Ludloff and Others v. United States, Justice Field delivered a dissenting opinion in which he argued that the majority's decision was wrongfully decided. He believed that the government had no right to take possession of land owned by private citizens without just compensation as required by the Fifth Amendment. In his view, it was unconstitutional for Congress to pass an act allowing them to do so without providing any form of payment or other consideration for taking away property from its rightful owners. Furthermore, he argued that even if such an act were constitutional, it should not be applied retroactively because doing so would violate due process rights under Article I Section 10 Clause 1 of the Constitution. As such, Justice Field concluded that since there was no justifiable reason why Congress could have taken this action against these individuals without providing proper compensation or other considerations for their loss of property rights then they must be compensated accordingly according to law and justice demands it.