Read 28 U.S.C. §1332:
(a) The district courts shall have original jurisdiction of all civil actions where the matter in controversy exceeds the sum or value of $75,000, exclusive of interest and costs, and is between–
(1) citizens of different States;
(2) citizens of a State and citizens or subjects of a foreign state;
(3) citizens of different States and in which citizens or subjects of a foreign state are additional parties; and
(4) a foreign state, defined in section 1603(a) of this title, as plaintiff and citizens of a State or of different States.
For the purposes of this section, section 1335, and section 1441, an alien admitted to the United States for permanent residence shall be deemed a citizen of the State in which such alien is domiciled. (b) Except when express provision therefor is otherwise made in a statute of the United States, where the plaintiff who files the case originally in the Federal courts is finally adjudged to be entitled to recover less than the sum or value of $75,000, computed without regard to any setoff or counterclaim to which the defendant may be adjudged to be entitled, and exclusive of interest and costs, the district court may deny costs to the plaintiff and, in addition, may impose costs on the plaintiff. (c) For the purposes of this section and section 1441 of this title–
(1) a corporation shall be deemed to be a citizen of any State by which it has been incorporated and of the State where it has its principal place of business, except that in any direct action against the insurer of a policy or contract of liability insurance, whether incorporated or unincorporated, to which action the insured is not joined as a party-defendant, such insurer shall be deemed a citizen of the State of which the insured is a citizen, as well as of any State by which the insurer has been incorporated and of the State where it has its principal place of business; and
(2) the legal representative of the estate of a decedent shall be deemed to be a citizen only of the same State as the decedent, and the legal representative of an infant or incompetent shall be deemed to be a citizen only of the same State as the infant or incompetent.
(d) The word “States”, as used in this section, includes the Territories, the District of Columbia, and the Commonwealth of Puerto Rico.