The present paper must be interpreted as a sequel of the work “Daten zu Leben und Werk des Pariser Architekten Charles Moreau zwischen 1760 und 1803”published in the Österreichische Zeitschrift für Kunst- und Denkmalpflege, Heft 4, 2001. This essay was finished when Moreau came to Vienna in the company of Prince Nikolaus II Esterházy at the end of 1803. The prince engaged the architect in Paris to lead the future works for the renewal of the family residence at Eisenstadt forming part of Hungary at this time. Moreau was quatered in the “Rothen Haus”which was situated in the Viennese suburb Alsergrund. In 1794 Prince Nikolaus II Esterházy became owner of the big family estates in the kingdom of Hungary. Shortly after his installation he engaged the French architect Jean-François Thomas de Thomon. He was responsible for the redesign of the garden of Nikolaus II in the Viennese suburb Landstraße, which was finished already in 1795. Surprisingly Thomas de Thomon quit his contract at the beginning of 1798 and went to Russia where he became architect of the tsar. Only at the end of 1802 Prince Esterházy employed another architect trained in Paris and Rome, Maximilian von Verschaffelt. Verschaffelt can be associated with the redesign of the garden in Eisenstadt and the alteration of the orangery still under construction. The other activities of Verschaffelt are not at hand. It seems that he was dismissed by the prince in favor of Charles Moreau in 1804. There is a good reason to believe that from 1804 on the activities followed to the directives of Charles Moreau because the first buildings invented and drawn by the architect were realized also at this time. In July 1804 the prince ordered the construction of the Marientempel which was situated north-west of Eisenstadt at the hillside of the Leithagebirge. At the same time the prince decreed the project for the Marientempel, he instructed the building department to start the works for the Maschinenhaus which was the first building designed by Charles Moreau for the landscape-garden. Among others it had to bare the steam-engine bought by the prince in London in 1803. Besides the mentioned activities the redesign of the old castle of Eisenstadt was started. According to the proposals of Charles Moreau the Prince ordered the beginning of the works in March 1805. First of all a passage under the north-wing and the basement for a representative portico flanked by two big ramps leading into the colonnade had to be constructed. Nikolaus II also started a project in Vienna in 1805. The work began in May 1805 and was not finished until 1807. Besides the works for Prince Nikolaus II Esterházy another client asked Moreau to design a palace in the city of Vienna. Elzbieta Anna Teofila Princess Lubomirska wanted to redesign several houses at the Mölkerbastei which defined an inner court. In the middle of 1806 Charles Moreau had to go back to Paris. He had been employed since the beginning of 1801 as “Architecte de la Sorbonne”. There is a good reason to believe that during his sojourn in Paris he visited not only his relatives but also his teachers, friends and old colleques. Virtually all of them were near Jacques-Louis David, the former teacher of Charles Moreau: Dominique Vivant Denon, François-Pascal-Simon Gérard and Antoine-Jean Gros, Charles-Paul Landon rival of Moreau and winner of the Grand prix de peinture as well as, among others, Jean-Baptiste Isabey who became a close collaborator of the architect during the Congress of Vienna. Although Nikolaus II was confronted with a proposal for the alteration and rearrangement of the so-called “Sauerbrunn”near Pöttsching – a new bath was mentioned for this place in 1805 – he decided to invest into the enlargement of a similar building already existing in Großhöflein. But at the beginning of 1807 there must have been some change of opinion and Charles Moreau was ordered to design a new bath not far from the old one. Another work of Moreau is located in Laxenburg where the Prince was responsible for the royal post-office and all its arrangements. It seems that the old station was too small. Therefore Nikolaus II ordered to enlarge the building by putting on a new flat and stables in 1805. He was also working on the new landscape gardens of the prince. When the garden of Pottendorf was nearly finished new hothouses were planned and built from the end of 1807. It was also in 1807 when the Prince possibly animated by the new constructions at Pottendorf ordered to construct new hothouses at Eisenstadt. A virtually new challenge was the design for a big festival-hall in the Viennese suburb, Schottenfeld, for which the Englishman Sigmond Wolfson made available his house and garden. The works for the building which consisted of several large rooms with different decorations was started in April 1807 and already finished in December of the same year. During the past years Charles Moreau and his family settled down in Vienna. In 1807 the painter Karl Johann Hummel charged him to design a new bath in the Viennese suburb Leopoldstadt. Moreau accepted and on Januray 1, 1808, they bought a big site near the Donaukanal. The idea to integrate the residences of both families into the complex must have been born at this time. Beside his activities in the service of Prince Esterházy, mainly in Eisenstadt, he was also commissioned to do other works. In 1811 Count Nikolaus Eszterházy gave a charge to the princely architect to redesign three houses situated between Walfischgasse and Krugerstraße in Vienna. The second work of Charles Moreau for the Count Esterházy was the design for a mausoleum for the deceased members of the family. Nagyganna was selected for it because of its geographical qualities. Also Count Johann Pálffy gave a contract to Charles Moreau. The count acquainted two houses in the Wallnerstraße in Vienna which were desolate from a fire-hazard. Moreau was ordered to redesign both buildings into a palace. The works done by Moreau in Austria and Hungary gave a lot of sympathy to the architect. The honoration was going so far that the council of the Akademie der vereinigten bildenden Künste in Vienna elected him as regular counsellor in 1812. Since Emperor Franz I did not confirm the decision there must have been some problems caused by the fact that Charles Moreau was no regular member of the institution at this time. So he became member of the academy in February 1812 and three months later he was nominated again for counsellor. But first on January 15, 1813, the emperor signed the letter of appointment.