1931年“九一八”事变后,日本帝国主义侵占了东北;进而把侵略的矛头指向华北。1933年4月,日军侵占热河,进逼平津,前锋抵达塘沽、通州。国民党政府代表熊斌、殷汝耕与日本关东军代表冈村宁次,在塘沽进行停战谈判。
        1933年5月31日,双方签订《塘沽协定》,规定日军撤至“长城一线” ,划绥东、察北、冀东一带22个县为“非武装区” ,中国不得驻有军队,允许日军自由出入。国民党政府实际上承认了日军侵占东三省和热河的合法化; 并把察北、冀东出卖给日本,为日军侵略华北提供了条件。
        1933年6月1日,中华苏维埃临时中央政府发表宣言,反对《塘沽协定》,严厉谴责国民党政府的卖国行径。
        《塘沽协定》签订以后,日军侵华活动日益猖獗。1934年8月,日本陆海军在大沽口外进行联合演习,海军14艘军舰发炮封锁大沽口外海面。
        1935年,日本侵略者借口中国当局援助东北义勇军孙玉勤部,进入冀东非武装区,破坏了《塘沽协定》,遂调遣关东军入关,进行威胁。7月6日,国民党北平军分会委员长何应钦,答应日华北驻屯军司令梅津美治郎提出的全部要求,撤销中国驻河北省的党政机关和军队,并禁止一切抗日活动,致使整个华北置于日军监视之下。
        1935年11月25日,国民党冀东行政督察专员殷汝耕,成立伪冀东防共自治政府,在塘沽驻设保安大队,为日军全面开放大沽海口。1936年初,日军在港口内增设海军码头,控制内河航运。同年12月,日海军部命令旅顺第14驱逐舰队的“菊” 、“获” 、“葵”号3艘驱逐舰,驶抵塘沽。
        1935年,日军还在大沽购置土地,策划建立海军陆战队营地,企图长期盘踞海口。日本从国内征集的2万余辆运输汽车,也通过大沽口,陆续运至天津。日本邮船株式会社的 “摩耶丸” 、“生驹丸”等船,每天由日本向塘沽运送军火。日本海军舰船经常来往于大连和塘沽之间,运送兵员与装备,为发动七七事变做准备。
        After the September 18 Event in 1931,Japaneseimperialists invaded the Northeast China. Its nextobjective was North China. In April,1933,the Japanesearmy occupied Rehe and menaced Beijing and Tianjin.Its pioneer force reached Tanggu and Tongzhou. TheKuomintang government sent Xiong Bin and YinRugeng to negotiate about truce with the JapaneseArmy`s representative Hideki Tojo at Tanggu.
        On May 31,1933,the two parties signed TangguTreaty which stipulated that the Japanese army retreatedto the line of Great Wall. Kuomintang allocated 22counties of the east of Sui,the north of Cha and theeast of Ji as "Non-Military Area" where Chinese couldnot be stationed and the Japanese could enter withoutresistance. In fact,the Kuomintang government admittedthe legitimation of the Japanese occupation of theprovinces of Northeast China and Rehe. It also gaveaway the north of Cha and the east of Ji to Japan,whichprovided convenience to Japan of invading north China.
        On June 1,1933,the temporary central governmentof Soviet China issued manifesto against Tanggu Treatyand criticized the betrayal of Kuomintang government.
        After the signing of Tanggu Treaty,the Japanesearmy was more active. In August,1934,the land forceand navy of Japan held joint maneuvers at Dagukou. 14warships of the navy blocked Dagu Seaport.
        In 1935,the Japanese army entered the nonmilitaryarea of the east of Ji in the pretext of Chinese governmentwas aiding Sun Yuqin`s Northeast Militia,which violatedthe Tanggu Treaty. It sent Kwantung Army to enterShanhaiguan. On July 6,He Yingqin,Chairman of theMilitary Committee of Peking Army of Kuomintang,accepted Umezu Yoshijro`s total requirements (thecommander of the Japanese army stationed in NorthChina). All government agencies and army of HebeiProvince retreated and stopped anti-Japan activities,which put north China under the scout of the Japanesearmy.
        On November 25,1935,Yin Rugeng,superintendentof east Ji area of Kuomintang,established JidongAnti-Communism Government. He organized peacepreservation corps at Tanggu and opened Dagu seaportto Japan. At the beginning of 1936,Japan set up navyport at Dagu to control the navigation of inland rivers.In December,the Japanese navy sent 3 chasers of "Ju","Huo" and "Kui" from its 14th fleet at Lushun to Tanggu.
        In 1935,the Japanese army bought lands at Daguto build the barrack of its marine corps,which intendedto occupy the seaport in a long period. About 20,000trucks arrived at Tianjin via Dagu seaport. The ships ofJapanese Postage Shipping Company carried weaponsfrom Japan to Dagu everyday. The warships of Japancarried soldiers and equipments between Dalian andTanggu,preparing for the breakout of the 7.7 Event.

        

·中日签订《塘沽协定》时合影