. ▁Block ed ▁from ▁further ▁advance ▁south ▁by ▁the ▁Tang gu ▁Tru ce , ▁the ▁Imperial ▁Japanese ▁Army ▁turned ▁its ▁attention ▁west , ▁towards ▁the ▁Inner ▁Mong ol ian ▁provinces ▁of ▁Ch ah ar ▁and ▁S ui y uan , ▁with ▁the ▁goal ▁of ▁establish ing ▁a ▁northern ▁China ▁buffer ▁state . ▁In ▁order ▁to ▁avoid ▁over t ▁viol ation ▁of ▁the ▁Tru ce , ▁the ▁Japanese ▁government ▁used ▁proxy ▁arm ies ▁in ▁these ▁campaign s ▁while ▁Chinese ▁resistance ▁was ▁at ▁first ▁only ▁provided ▁by ▁Anti - J apan ese ▁resistance ▁movement ▁forces ▁in ▁Ch ah ar . ▁The ▁former ▁included ▁in ▁the ▁Inner ▁Mong ol ian ▁Army , ▁the ▁Man ch u ku o ▁Imperial ▁Army , ▁and ▁the ▁Grand ▁Han ▁R igh te ous ▁Army . ▁Chinese ▁government ▁forces ▁were ▁over t ly ▁host ile ▁to ▁the ▁anti - J apan ese ▁resistance ▁and ▁resist ed ▁Japanese ▁ag gression ▁only ▁in ▁S ui y uan ▁in ▁ 1 9 3 6 . ▁ ▁Background ▁ ▁In ▁February ▁ 1 9 3 3 , ▁following ▁the ▁successful ▁Japanese ▁invasion ▁of ▁Je hol , ▁the ▁K w ant ung ▁Army ▁left ▁a ▁small ▁Japanese ▁det achment ▁and ▁the ▁much ▁larger ▁Man ch u ku o ▁Imperial ▁Army ▁to ▁watch ▁the ▁eastern ▁Je hol ▁border , ▁while ▁the ▁balance ▁of ▁the ▁Japanese ▁forces ▁moved ▁south ▁to ▁eng age ▁the ▁Chinese ▁on ▁the ▁Great ▁Wall . ▁In ▁April ▁ 1 9 3 3 , ▁collaboration ist ▁General ▁Li u ▁Gu it ang , ▁under ▁Japanese