War was declared on 20 April 1792 against the King of Bohemia and Hungary (Austria). The initial battles were a disaster for the French, and Prussia joined Austria in active alliance against France. The blame for the disaster was put upon the King and his ministers (the Austrian Committee), and after upon the Girondin party.
The Legislative Assembly passed decrees sentencing any priest denounced by 20 citizens to immediate deportation (17 May), dissolving the King's guard because it was manned by aristocrats (29 May), and establishing in the vicinity of Paris a camp of 20,000 Fédérés (8 June). The King vetoed the decrees and dismissed Girondists from the Ministry. When the King formed a new cabinet mostly of constitutional monarchists (Feuillants), this widened the breach between the King and the Assembly and the majority of the common people of Paris. These events happened on 16 June when Lafayette sent a letter to the Assembly, recommending suppression of "anarchists" and political clubs in the capital.
The King's veto of the Legislative Assembly's decrees was published on 19 June, one day before the 3rd anniversary of the Tennis Court Oath, which had inaugurated the Revolution. The popular journée of 20 June 1792 was organized to put pressure on the King. Appearing before the crowd, the King put on the bonnet rouge of liberty and drank to the health of the nation, but refused to ratify decrees or to recall the ministers. The Paris mayor, Pétion, was suspended. On 28 June, Lafayette left his post with the army and appeared before the Assembly to call on the deputies to dissolve the Jacobin Club and punish those who were responsible for the demonstration of 20 June. The deputies indicted the general for deserting his command. The King rejected all suggestions of escape from the man who had long presided over his imprisonment. The crowd burnt him in effigy at the Palais-Royal. There was no place for Lafayette beside the republican emblem, nor in the country which had adopted it. Within six weeks he was arrested whilst fleeing to England and immured in an Austrian prison. Lafayette failed because his views clashed with French national sentiment, and his passive leadership of French armies had given the Prussians time to finish their preparations and concentrate upon the Rhine undisturbed.
A decree of 2 July authorized national guards, many of whom were already on their way to Paris, to come to the Federation ceremony. A decree of 5 July declared that in the event of danger to the nation all able-bodied men could be called to service and necessary arms requisitioned. Six days later the Assembly declared la patrie est en danger (the homeland is in danger). Banners were placed in the public squares, with the words:
Would you allow foreign hordes to spread like a destroying torrent over your countryside! That they ravage our harvest! That they devastate our fatherland through fire and murder! In a word, that they overcome you with chains dyed with the blood of those whom you hold the most dear... Citizens, the country is in danger!