Editing First Battle of the Marne (section)

=== Bülow and Hausen ===
Bülow's 2nd army south of the Marne on 6 September was as worn and depleted as Kluck’s, having marched {{cvt|440|km|mile}} since leaving Germany and having suffered more than 26,000 casualties and soldiers felled by illnesses. Bülow had begun the war with 260,000 soldiers; in September he had 154,000. Moreover, his relations with Kluck were poor.{{sfn|Herwig|2009|pages=234–235, 250–251}}

While Kluck was on the offensive near Paris, Bülow went on the defensive after the French attack on 6 September. On 7 September, Bülow ordered his right wing to retreat {{cvt|15|km|mile}} to the [[Petit Morin River]] after attacks by the French 5th army of [[Franchet d'Esperey]], called "Desperate Frankie" as a compliment by the British. During the retreat, the French massacred 450 Germans who were attempting to surrender. With his right wing retreating, Bülow conversely ordered his left wing to attack with help from Hausen's 3rd army.{{sfn|Herwig|2009|pages=235–236, 248–251}}  Hausen covered Bülow's left flank and assaulted Foch's 9th army in the Marshes of Saint–Gond near the city of [[Sézanne]] on 8 September. He had 82,000 men for the task. Hausen's attack was a surprise, launched at night with no artillery preparation. His soldiers overran artillery positions "with the bayonet." Hausen pushed Foch back {{cvt|13|km|mile}}. Hausen's attack then bogged down with his soldiers exhausted and having suffered about 11,000 casualties.{{sfn|Herwig|2009|pages=255–261}}{{sfn|Keegan|1998|pages=118–119}}and also