Whether “laws of the several States,” as so used, included nonstatutory law embodied in judicial decisions of state courts was long a subject of controversy. After acting for half a century on the belief that it did, the court, in Swift v. Tyson, 16 Pet. 1, decided that it did not. Almost a century later, that decision, with it numerous and sorry progeny, was overruled, and the Court answered that it did. Erie R. Co. v. Tompkins, supra. It later held that state decisions on conflicts of laws were also binding on the federal courts. Klaxon v. Stentor Electric Mfg. Co., 313 U.S. 487 (1941). Thus, the Rules of Decision Act, as now interpreted, requires federal courts to use state law, whether declared by the legislature or by the courts, as rules of decision “in cases where they apply,” except where federal law shall “otherwise require or provide.” These recent cases, like Swift v. Tyson, which evoked them, dealt only with the very special problems arising in diversity cases, where federal jurisdiction exists to provide nonresident parties an optional forum of assured impartiality. [315 U.S. 467] The Court has not extended the doctrine of Erie R. Co. v. Tompkins beyond diversity cases. … many subjects of private law which bulk large in the traditional common law are ordinarily within the province of the states, and not the federal government. From O’Dench Dume v. FDIC, 315 U.S. 447 In addition, O’Dench Dume tells us that the Federal Court system is bound by the state’s views as to whether there is a contract. Quoting, “…[W]e are not bound by the state’s views as to whether there is a contract.” This is why they are free to construct a trust and take jurisdiction.