The assault on the Amigny heights, crossing the Oise at Chauny, the attack on Coucy le Chateau and the chase to the Oise-Aisne canal from the 6th-9th of April 1918

During the Kaiserschlacht the Northern Wing of the 7th Army had an eye on the Oise bend to the South West of La Fere.  

Units of the 7th Army had been transferred North to take part in the Kaiserschlacht and given the lack of troops the attack had been postponed. On the 6th of April, after the Kaiserschlacht had ground to a halt "Operation Archangel" was launched.

Operation Archangel: The Shaded area to the North of Chauny was land gained in the Michel offensive. The dark triangle to the South of Chauny is the land gained in Operation Archangel. The operation secured the southern flank of the 18th Army and straightened the sector of front held by the 7th army. A brief section on the fighting on the Southern flank of the 18th Army can be found HERE

Generaloberst Max von Boehn, commander of the 7th Army

The British and French soldiers to the North of the Oise-Aisnes canal were not in an enviable position. The wedge shaped salient intruded into the German line and could be attacked from the North West and from the East, an opportunity that the Germans could barely be expected to miss seeing.  

Crossing the Oise at Chauny the VIII Armee Korps advanced while the VIII Reserve Korps attacked from the east.

  At 3.30 am on the morning of the 6th of April the German artillery opened fire, the allied response was negligible. The VIII Korps took Chauny, threw 2 pontoon bridges over the Oise, fought off a counter attack then advanced forming a front stretching from Abbecourt-Bichancourt-Sinceny. The VIII Reserve Korps stormed the twin heights at Amigny and continued on into the forest of Coucy. Halfway through the forest they reached the Chauny to Barisis Railwayline.

This unexpectedly rapid success netted not only 900 POWs but also a block of land 10km wide and 6km deep.   +

The next day the enemy defences wilted under the pressure of the German assault divisions. The rest of the forest of Coucy was taken and a line was reached that stretched from Champs (on the Ailette) through Folembray to Fresne.  

The Heights of Coucy le Chateau were the final objective of this limited offensive. They dominated the surrounding area and were defended by the French artillery on the Southern bank of the Ailette. The Allied troops at Coucy fought tenaciously and it seemed that they would succeed in holding off the Germans but on the afternoon of the 8th of April the attackers reached the foot of the slopes.

The German artillery struggled forward through the wooded ravines looking for positions from which they could support the final push. Just before nightfall all was ready. The Storm troops rose for a final attempt. Supported by the artillery they breached the walls and took the position.

On the 9th of April, the last day of the offensive the canal and the Ailette were reached along the length of the German advance. The French artillery was pushed onto the Southern bank of the river.

The goals achieved by the offensive was that the flank of the Southern wing of the 18th Army was now protected and in its new positions  the 7th army had shortened the length of frontline it needed to defend.