I know of no sufficient warrant for declaring that any rule of international law, concerning the recognition, in that State, of a change of _status_, wrought by an extra-territorial law, has been displaced or varied by the will of the State of Missouri. I proceed then to inquire what the rules of international law prescribe concerning the change of _status_ of the plaintiff wrought by the law of the Territory of Wisconsin. It is generally agreed by writers upon international law, and the rule has been judicially applied in a great number of cases that wherever any question may arise concerning the _status_ of a person, it must be determined according to that law which has next previously rightfully operated on and fixed that _status_. And, further, that the laws of a country do not rightfully operate upon and fix the _status_ of persons who are within its limits _in itinere_, or who are abiding there for definite temporary purposes, as for health, curiosity, or occasional business; that these laws, known to writers on public and private international law as personal statutes, operate only on the inhabitants of the country. Not that it is or can be denied that each independent nation may, if it thinks fit, apply them to all persons within their limits. But when this is done, not in conformity with the principles of international law, other States are not understood to be willing to recognise or allow effect to such applications of personal statutes. It becomes necessary, therefore, to inquire whether the operation of the laws of the Territory of Wisconsin upon the _status_ of the plaintiff was or was not such an operation as these principles of international law require other States to recognise and allow effect to. And this renders it needful to attend to the particular facts and circumstances of this case. It appears that this case came on for trial before the Circuit Court and a jury, upon an issue, in substance, whether the plaintiff, together with his wife and children, were the slaves of the defendant.