Anderson v. Santa Anna is a United States Supreme Court case that was decided in 1886. The case involved a dispute between two parties over a contract for the sale of land in Mexico. The plaintiff, Anderson, was a citizen of the United States who had purchased a tract of land in Mexico from Santa Anna, a Mexican citizen. Anderson alleged that Santa Anna had breached the contract by failing to deliver the deed to the land. The Supreme Court held that the contract was valid and enforceable under the law of nations. The Court reasoned that the contract was valid because it was made between two citizens of different countries, and the law of nations requires that contracts between citizens of different countries be respected. The Court also held that Anderson was entitled to damages for the breach of contract. In conclusion, the Supreme Court held that Anderson was entitled to damages for the breach of contract and that the contract was valid and enforceable under the law of nations. The Court's decision established that contracts between citizens of different countries must be respected and enforced.

Justice Field delivered the dissenting opinion in Anderson v. Santa Anna, arguing that a foreign government cannot be sued without its consent. He argued that this was an established principle of international law and had been recognized by the Supreme Court since 1812. Furthermore, he noted that it would be inappropriate for a court to interfere with diplomatic negotiations between two countries over matters such as debt collection or other disputes. Therefore, Justice Field concluded that the lower court's decision should have been affirmed and not reversed on appeal because there was no basis upon which to sue Santa Anna in U.S courts without his consent or permission from his own government first being obtained.