[1] By the end of May 1940, the best-equipped French armies had been sent north and lost in Fall Gelb and the evacuation from Dunkirk, which cost the Allies 61 divisions.

Weygand lacked reserves to counter a breakthrough against 142 German divisions and the Luftwaffe, which had air supremacy, except over the English Channel.

[2] Between six and ten million civilian refugees had fled the fighting and clogged the roads, in what became known as L'Éxode (The Exodus) and few arrangements had been made for their reception.

Behind that, the new infantry, armoured and half-mechanised divisions were ready to counter-attack and relieve the surrounded units, which were ordered to hold out at all costs.

[11] South of Abbeville, the French Tenth Army (General Robert Altmayer) had its front broken and it was forced to retreat to Rouen and southwards over the Seine river.

[12] German spearheads were overextended and vulnerable to counter strokes but the Luftwaffe denied the French the ability to concentrate and the fear of air attack negated their mass and mobile use by Weygand.

[15] On 14 June, Paris fell and the Parisians unable to flee the city found that in most cases the Germans were extremely well mannered.

The RAF attempted to divert the attention of the Luftwaffe with 660 sorties flown against targets over the Dunkirk area but lost many aircraft; on 21 June, 37 Bristol Blenheims were destroyed.

The goal of the operation was to envelop the Metz region, with its fortifications, to prevent a French counter-offensive from Alsace against the German line on the Somme.

The Germans greatly outnumbered the French and could call upon I Armeekorps of seven divisions and 1,000 guns, although most were First World War vintage and could not penetrate the thick armour of the fortresses.

The Luftwaffe deployed Fliegerkorps V.[19] The battle was difficult and slow progress was made against strong French resistance but the fortresses were overcome one by one.

Five assault divisions of the VII Armeekorps crossed the Rhine into the Colmar area with a view to advancing to the Vosges Mountains.

On 17 June, Junkers Ju 88s (mainly from Kampfgeschwader 30) sank a "10,000 tonne ship" which was the 16,243 GRT liner RMS Lancastria off St Nazaire, killing some 4,000 Allied personnel (nearly doubling the British killed in the Battle of France), yet the Luftwaffe failed to prevent the evacuation of some 190,000–200,000 Allied personnel.

He was succeeded by Marshal Philippe Pétain, who delivered a radio address to the French people, announcing his intention to ask for an armistice with Germany.

[23] On 21 June 1940, Hitler visited the site to start the negotiations, which took place in the railway carriage in which the 1918 Armistice was signed.

[24] After listening to the preamble, Hitler left the carriage in a calculated gesture of disdain for the French delegates and negotiations were turned over to Wilhelm Keitel, the Chief of Staff of Oberkommando der Wehrmacht (OKW).

The two sides exchanged air raids on the first day of war but little transpired on the Alpine front, since both France and Italy had adopted a defensive strategy.

There was some skirmishing between patrols and the French forts of the Ligne Alpine exchanged fire with their Italian counterparts of the Vallo Alpino.