Jean-Xavier Bureau de Pusy

 Jean-Xavier Bureau de Pusy (born 7 January 1750 at Port-sur-Saône in the department of Haute-Saône – died 2 February 1806 in Genoa, Italy) was a French military engineer, and politician, during the French Revolution.

Military career
He was a military engineer at the Fort de Joux in 1786, in 1789 he was captain with the Royal corps of Engineers.

Political career
Deputy of nobility with the National Constituent Assembly, Jean-Xavier Bureau of Pusy was three times named chair:
 * from 2 to 24 February 1790;
 * from 11 to 24 September 1790;
 * from 24 May to 5 June 1791.

He contributed actively to the division of France into 83 departments, in 1790, and with the metric system.

In 1790, he corresponded with Alexander Hamilton.

In 1792. he was a subordinate under Gilbert du Motier, marquis de Lafayette, at Metz. He was captured at Rochefort, Belgium, and imprisoned by the Austrians at the fortress of Olmütz in 1792. He was released in 1797, under the terms of the treaty of Campo-Formio (18 October 1797).

First Empire
He visited the United States, and was prefect under First Empire. In 1799, he corresponded with Thomas Jefferson.

His son, Maurice de Pusy (1799–1864), married Mathilde de Lafayette, daughter of Georges de Lafayette and Emilie de Tracy, and granddaughter of General Lafayette and Destutt de Tracy.