The Girondin majority in the Legislative Assembly favoured war, especially with Austria, in order to display the Revolution's strength and defend its achievements (such as the Declaration of the Rights of the Man and of the Citizen of 1789 and the early beginnings of parliamentary democracy) against a possible return to an absolutist Ancien Régime.

Major-general Charles François Dumouriez was appointed to Minister of Foreign Affairs in March 1792, and by mid-April had managed to obtain the neutrality of all European great powers except Austria and Prussia through cunning diplomacy.

[2] The French army was plagued by troubles: both Lafayette and Rochambeau were convinced royalists, and had doubts about the republican minister's intentions as well as the feasibility of his strategies; the troops were poorly equipped, many of them untrained volunteers, and they distrusted their aristocratic officers; and finally, queen Marie Antoinette (herself an Austrian, and rightfully fearing that further republican radicalisation would cost her life) secretly passed on this and later war plans to the Austrian government in Brussels, with king Louis' approval.

[2] Leaving Lille with 10 squadrons, 6 battalions and 6 guns, he met the Austrian major-general Louis-François de Civalart, encamped with 3,000 men on the heights above Marquain.

Seeing the enemy coming down to meet him and unsure of his own troops (who had frequently been insubordinate on the march from Lille), Dillon obeyed his orders and commanded a retreat.

[2] The complete failure of the Belgian invasion was a great humiliation for the members of the Legislative Assembly, where the leftist Jacobins blamed the Girondins and both accused the royal family of conspiring with the Austrian and Prussian enemy, which was true.