First Battle of the Aisne The First Battle of the Aisne ( ) was the Allied follow - up offensive against the right wing of the German First Army ( led by Alexander von Kluck ) & Second Army ( led by Karl von Bülow ) as they retreated after the First Battle of the Marne earlier in September 1914 . The offensive began on the evening of 13 September , after a hasty pursuit of the Germans . Battle . When the Germans turned to face the pursuing Allies on September 13 , they held one of the most formidable positions on the Western front . Between Compiègne and Berry - au - Bac , the Aisne River winds westward and is about one hundred feet wide , ranging from twelve to fifteen feet deep . Low - lying ground extends a mile on each side , rising abruptly to a line of steep cliffs three to four hundred feet high , then gently leveling to a plateau . The Germans settled on the higher northern side two miles ( 3 km ) beyond the crest , behind a dense thicket that covered the front and slope . Low crops in the unfenced countryside offered no natural concealment to the Allies . Deep , narrow paths cut into the escarpment at right angles , exposed infiltrators to extreme hazard . The forces on the northern plateau commanded a wide field of fire . In a dense fog on the night of September 13 , most of the BEF crossed the Aisne on pontoons or partially demolished bridges , landing at Bourg - et - Comin on the right and at Venizel on the left . At Chivres east of Venizel was an escarpment the Germans had selected as their strongest position . The French Fifth Army crossed the Aisne at Berry - au - Bac and captured the eastern tip of Chemin des Dames , a steep ridge named after the royal coach road Louis XV had built for his daughters . Contact was established along the entire front . East of Chemin des Dames , the French Fourth , Fifth and Ninth armies made only negligible progress beyond the positions they had reached on September 13 . Under the thick cover of the foggy night , the BEF advanced up the narrow paths to the plateau . When the mist evaporated under a bright morning sun , they were mercilessly cross - raked by fire . Those caught in the valley without the fog ' s protective shroud fared no better . Trench warfare begins . It soon became clear that neither side could budge the other and since neither chose to retreat , the impasse hardened into stalemate that would lock the antagonists into a relatively narrow strip for the next four years . On September 14 , Sir John French ordered the entire BEF to entrench but few digging tools were available . Soldiers scouted nearby farms and villages for pickaxes , spades and other implements . Without training for stationary warfare , the troops merely dug shallow pits in the soil . These were at first intended only to afford cover against enemy observation and shell fire . Soon the trenches were deepened to about seven feet . Other protective measures included camouflage and holes cut into trench walls then braced with timber . Trench warfare was also new for the Germans , whose training and equipment were designed for a mobile war to be won in six weeks , but they quickly adapted their weapons to the new situation . Siege howitzers now lobbed massive shells into Allied trenches . Skillful use of trench mortars , rifle grenades and hand grenades ( first used against British troops on September 27 ) , enabled the Germans to inflict great injuries upon Allied troops , who had neither been trained nor equipped with these weapons . Searchlights , flares and periscopes were also part of the German equipment intended for other purposes but put to use in the trenches . A shortage of heavy weapons handicapped the British . Only their 60 - pounders ( four to a division ) were powerful enough to shell enemy gun emplacements from the Aisne ' s south shore , and these guns were inferior to German artillery in caliber , range and numbers . Four batteries of guns ( a total of sixteen ) were rushed from England . Though a poor match against the German howitzers , they helped somewhat . Defensive firepower was limited to rifles and two machine guns alloted to each battalion . The British regulars were excellent marksmen but even their combined accuracy was no match for the German machine guns and grenades . The British had equipped very few of their aeroplanes with wireless and they were used to report troop movements . It was only natural for aviators to recognize the advantage of observing artillery fire . On September 24 , Lieutenants B . T . James and D . S . Lewis detected three well - concealed enemy gun batteries that were inflicting considerable damage on British positions . They radioed back the location of the batteries , then droned in a wide circle waiting to spot their own gunners ' exploding shells . Anti - aircraft fire was desultory and inaccurate . The German army used only percussion shells of which , according to Canadian sources , " not one in several hundred ever hit its aerial target , and fell to earth frequently at some point in the British lines and there burst . " Race to the Sea . For a three - week period following the unexpected development of trench warfare , both sides gave up frontal assaults and began trying to encircle each other ' s northern flank . The period is called " Race to the Sea . " As the Germans aimed for the Allied left flank , the Allies sought the German right wing . The western front thus became a continuous trench system of more than . From the Belgian channel town of Nieuport , the trench lines ran southward for some hundred miles , turning southeast at Noyon continuing past Reims , Verdun , Saint - Mihiel and Nancy ; then cutting south again to the northern Swiss border twenty miles ( 32 km ) east of Belfort . The BEF , left exhausted by the Aisne battle , remained relatively inactive . It was mainly the French who engaged the Germans in the " Race " but the British grew increasingly alarmed as the Germans advanced towards the coast . Winston Churchill , First Lord of the Admiralty , determined to prevent the Germans from capturing other channel ports which could be used as bases to attack English shipping . In late September , he arrived in France to arrange the transfer of the BEF to the north . By October 10 all but one corps had reached their staging areas in the Saint - Omer – Hazebrouck area , where the last camouflaged move was not detected by air reconnaissance until October 8 , too late to muster adequate forces against the British . Meanwhile , the Belgian Army became a growing threat to German communications as the battle shifted northward . The Germans made plans on September 28 to capture the port of Antwerp and crush the Belgian forces . This important maritime city was encircled by an obsolete fortress system that could not withstand even 6 - inch shells . An outer ring of eighteen forts ranged from seven to nine miles from the city , an inner ring from one to two miles . Each fort was armed with two machine guns , but lacked telephone communications and means for observing gunfire . One 6 - inch gun poked out at each mile , none of these forts had high explosive projectiles or smokeless gunpowder and several thousand surrounding acres had been cleared to provide unobstructed fields of fire . At daybreak on September 29 , General Hans von Beseler , called from retirement at the age of sixty - five , arrayed six divisions in an arc facing the outer ring of forts . The heavy siege howitzers that had destroyed the defenses of Namur and Liège had been placed well beyond the range of Belgian artillery . Aided by aircraft spotting , German gunners quickly found their targets . Belgian guns belched dense , black smoke puffs revealing their exact location and the fields cleared by the defenders deprived the forts of any concealment . Two of the forts were quickly reduced to rubble ; the others fell in methodical succession . Without waiting for the outcome , the Belgian government and 65 , 000 troops departed from Ostend that night , leaving an army of 80 , 000 to hold off the enemy . Next day the entire outer ring collapsed , prompting a mass evacuation of civilians to the neutral Netherlands . A British Royal Marine Division joined the defending troops during the attack , but even this combined force was unable to stem the German drive . After six days of stubborn fighting , the remaining garrison retired across the Scheldt River to the southern border of the Netherlands , while the rest of the Belgian army retreated to the South , subsequently attaching itself to General Foch ' s Ninth Army . Many of those killed at Aisne are buried at Vailly British Cemetery . There were two later battles on the Aisne ; The Second Battle of the Aisne ( April – May 1917 ) and the Third Battle of the Aisne ( May – June 1918 ) .