▁advanced ▁from ▁Mar le ▁on ▁the ▁Ser re , ▁across ▁the ▁A is ne ▁and ▁the ▁V es le , ▁between ▁Re ims ▁and ▁F ism es ▁to ▁Mont mort , ▁north ▁of ▁the ▁j unction ▁of ▁the ▁N inth ▁and ▁Fif th ▁Arm ies ▁at ▁Sé z anne . ▁The ▁Fif th ▁Army ▁and ▁the ▁BE F ▁had ▁with dra wn ▁south ▁of ▁the ▁O ise , ▁Ser re , ▁A is ne ▁and ▁Our q , ▁purs ued ▁by ▁the ▁ 2 nd ▁Army ▁on ▁a ▁line ▁from ▁Gu ise ▁to ▁La on , ▁V ail ly ▁and ▁D orm ans ▁and ▁by ▁the ▁ 1 st ▁Army ▁from ▁Mont did ier , ▁towards ▁Com pi èg ne ▁and ▁then ▁south - east ▁towards ▁Mont mi ra il . ▁The ▁new ▁French ▁Six th ▁Army , ▁linked ▁with ▁the ▁left ▁of ▁the ▁BE F , ▁west ▁of ▁the ▁Mar ne ▁at ▁Me aux , ▁to ▁P onto ise ▁north ▁of ▁Paris . ▁French ▁g arr isons ▁were ▁bes ie ged ▁at ▁Str as bourg , ▁Met z , ▁Th ion ville , ▁Long wy , ▁Mont m éd y ▁and ▁Ma ube uge . ▁The ▁Belg ian ▁army ▁was ▁inv ested ▁at ▁Ant werp ▁in ▁the ▁National ▁Red ou bt ▁and ▁at ▁Li ège , ▁for tr ess ▁troops ▁continued ▁the ▁defence ▁of ▁the ▁for ts . ▁ ▁Eastern ▁Front ▁ ▁Austria - H ung ary ▁had ▁declared ▁war ▁on ▁Ser bia ▁on ▁ 2 8 ▁July ▁and ▁on ▁ 1