Neumann was born in Brussels (then in the Austrian Netherlands), the son of Carl von Neumann (an official in the Habsburg administration) and his wife Marie Ducpetiaux. Nothing is known of his education, but, since he did not begin work until he was 21, it seems likely that he attended university. His brother was General-major Maximillian Ritter von Neumann (c1778-1846).
Nothing is known of his education, but, since he did not begin work until he was 21, it seems likely that he attended university.
Neumann began his career in the Austrian Treasury Service in 1802 and was posted to Venice which had come under Austrian control a few years previously. After just over a year he joined the diplomatic service and was posted to Paris where Prince Klemens Wenzel von Metternich was Austrian ambassador. Later Neumann joined the staff of the Austrian embassy in London under the ambassador Prince Esterházy.
Neumann served as chargé d"affaires in his absence.
Neumann"s activity was regarded as notable, especially in 1814 and 1815, on the occasion of the remittance of the British subsidies to the Austrian government, when he succeeded in obtaining very favourable conditions for Austria on the question of the rate of exchange. He described Castlereagh"s suicide as " a great mystery which perhaps time will explain".
In October of the following year he attended the negotiations on this matter carried on at Vienna. In December 1829 Neumann conducted the Treaty of Commerce between Austria and Great Britain.
In recognition of his services he was created a Baron by the Emperor Francis I of Austria on 31 August 1830.
In 1844 Neumann became Minister Plenipotentiary and Envoy Extraordinary for Austria to the Court of Saint James"son In 1845 he was appointed Austrian minister in Florence, and on 31 December 1849 he was appointed Austrian minister in Brussels.
