By a strange irony this event, the chief event of Lucien's life, was fatal to the cause of democracy of which he had been the most eager exponent. In one of his earlier letters to his brother Joseph, Lucien stated that he had detected in Napoleon "an ambition not altogether egotistic but which surpassed his love for the general weal; ... in case of a counter-revolution he would try to ride on the crest of events." Napoleon having by his help triumphed over parliamentary institutions in France, Lucien's suspicion of his brother became a dominant feeling; and the relations between them became strained during the period of the consulate (1799-1804). He accepted office as minister of the interior, but was soon deprived of it owing to political and personal differences with the First Consul. In order to soften the blow, Napoleon appointed him ambassador to the court of Madrid (November 1800). There again Lucien displeased his brother. France and Spain were then about to partition Portugal, and the Spanish forces were beginning to invade that land, when the court of Lisbon succeeded, owing (it is said) to the free use of bribes, in inducing Godoy, the Spanish minister, and Lucien Bonaparte to sign the preliminaries of peace on the 6th of June 1801 at Badajoz. The First Consul, finding his plans of seizing Lisbon frustrated, remonstrated with his brother, who thereupon resigned his post, and returned to Paris, there taking part in the opposition which the Tribunate offered to some of Napoleon's schemes. Lucien's next proceeding completed the breach between the two brothers. His wife had died in 1800; he became enamoured of a Mme Jouberthou in the early summer of 1802, made her his mistress, and finally, despite the express prohibition of the First Consul, secretly married her at his residence of Plessis (on October 23, 1803). At that time Napoleon was pressing Lucien for important reasons of state to marry the widow of the king of Etruria, and on hearing of his brother's action he ordered him to leave French territory. Lucien departed for Italy with his wife and infant son, after annoying Napoleon by bestowing on her publicly the name of Bonaparte. He also charged Joseph never to try to reconcile Napoleon to him.