Edmond-Charles Genêt was the French Ambassador during the Revolution.

He's more known for what's called the Genet affair, where he recruited help for the Revolutionary wars against England and Spain, giving out letters of Marque and Reprise for Americans interested in Privateering as well as organizing adventurers for Spanish Florida.

Washington sent a letter to John Jay, the chief justice of the Supreme Court to get his opinion about Genet's breaking US neutrality, (which is my primary source). Jay demurred (itself quite important for US law). In the end the Jacobians solved the problem by recalling him to kill him.

Genet asked for, and got asylum.

Sources: Matthew T. King, Towards a Practical Convergence: the Dynamic Uses of Judicial Advice in United States Federal Courts and the Court of Justice of the European Communities, 63 U. Pitt. L. Rev. 703, 705 (2002); (Citing The Correspondence and Public Papers of John Jay 486 (Henry P. Johnson ed., 1893)); See also David M. Golove & Daniel J. Hulsebosch, A Civilized Nation: the Early American Constitution, the Law of Nations, and the Pursuit of International Recognition, 85 N.Y.U. L. REV. 932, 1023 (2010) (suggesting Washington asked Jay to get an Anti-French answer, while Jay only denied the advisory opinion because a case was pending (Glass v. The Betsey, 3 U.S. 6, 9 (1794))).

I'm interested in the same question, but specifically in respects to the U.S.S.R. during its dissolution. Can someone provide some examples of what happened to Soviet diplomats?