在平定安(an)(an)史(shi)(shi)之亂得過程(cheng)中，為求(qiu)得暫時茍安(an)(an)，唐代宗(zong)措置失當，“瓜分河北地(di)，付授叛將(jiang)”，使(shi)安(an)(an)史(shi)(shi)降(jiang)將(jiang)搖身一變，成了由(you)中央任命的(de)節度(du)使(shi)，保存了相(xiang)當大的(de)離心力。在平叛過程(cheng)中，朝廷還(huan)對(dui)內地(di)掌握兵權的(de)刺史(shi)(shi)多加(jia)節度(du)使(shi)稱號，造成了亂后“方鎮相(xiang)望(wang)于內地(di)，大者連州十余，小者猶兼三四”的(de)藩鎮割據的(de)嚴重局面。
唐(tang)德(de)宗(zong)(zong)(zong)即位后，力圖削藩。建中二年(nian)（781）正(zheng)(zheng)月(yue)(yue)，成德(de)節(jie)度使(shi)李(li)(li)(li)寶臣死(si)，子李(li)(li)(li)惟岳(yue)向朝廷(ting)(ting)請(qing)求襲其(qi)父位，魏博節(jie)度使(shi)田悅(yue)亦(yi)代為之(zhi)請(qing)。德(de)宗(zong)(zong)(zong)堅決(jue)拒絕。李(li)(li)(li)、田遂(sui)聯合淄青節(jie)度使(shi)李(li)(li)(li)正(zheng)(zheng)己(ji)，山南(nan)(nan)東道(dao)節(jie)度使(shi)梁(liang)崇義等(deng)起兵(bing)反(fan)唐(tang)。七(qi)月(yue)(yue)李(li)(li)(li)正(zheng)(zheng)己(ji)死(si)，八月(yue)(yue)子李(li)(li)(li)納(na)(na)亦(yi)請(qing)襲父位，德(de)宗(zong)(zong)(zong)不(bu)允(yun)，李(li)(li)(li)納(na)(na)遂(sui)反(fan)。戰事日益擴大。建中四年(nian)正(zheng)(zheng)月(yue)(yue)，割據淮(huai)西（今河南(nan)(nan)汝南(nan)(nan)）的節(jie)度使(shi)李(li)(li)(li)希烈叛，攻(gong)(gong)襄城（今屬河南(nan)(nan)）。德(de)宗(zong)(zong)(zong)派(pai)哥舒曜討伐，未(wei)果。德(de)宗(zong)(zong)(zong)又(you)(you)派(pai)涇原(yuan)(yuan)兵(bing)去解圍。時涇原(yuan)(yuan)節(jie)度使(shi)朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)因其(qi)弟(di)朱(zhu)(zhu)(zhu)(zhu)(zhu)滔謀(mou)反(fan)而被軟禁(jin)于(yu)京城。涇原(yuan)(yuan)兵(bing)路過長(chang)安時，因賞賜不(bu)周(zhou)，挾持節(jie)度使(shi)姚令言嘩變。德(de)宗(zong)(zong)(zong)逃往奉天(tian)。叛軍推舉朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)為首領(ling)，史稱(cheng)(cheng)涇原(yuan)(yuan)之(zhi)變。朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)率軍攻(gong)(gong)奉天(tian)，未(wei)下。此時朝廷(ting)(ting)援兵(bing)已逼長(chang)安，朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)退守長(chang)安。不(bu)久唐(tang)將(jiang)領(ling)李(li)(li)(li)懷光與朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)聯合。德(de)宗(zong)(zong)(zong)被迫又(you)(you)奔梁(liang)州（今陜西漢中）。興元元年(nian)（784）五月(yue)(yue)，唐(tang)將(jiang)領(ling)李(li)(li)(li)晟等(deng)攻(gong)(gong)克長(chang)安，德(de)宗(zong)(zong)(zong)于(yu)七(qi)月(yue)(yue)返回。朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)被部下所殺。朱(zhu)(zhu)(zhu)(zhu)(zhu)滔病死(si)。李(li)(li)(li)懷光兵(bing)敗自縊(yi)。因在這次戰爭(zheng)中，有四人稱(cheng)(cheng)王(wang)，兩人稱(cheng)(cheng)帝(di)，即朱(zhu)(zhu)(zhu)(zhu)(zhu)滔稱(cheng)(cheng)冀王(wang)，王(wang)武俊(jun)稱(cheng)(cheng)趙王(wang)，田悅(yue)稱(cheng)(cheng)魏王(wang)，李(li)(li)(li)納(na)(na)稱(cheng)(cheng)齊王(wang)，朱(zhu)(zhu)(zhu)(zhu)(zhu)泚(ci)稱(cheng)(cheng)秦帝(di)，李(li)(li)(li)希烈稱(cheng)(cheng)楚帝(di)，故又(you)(you)稱(cheng)(cheng)二帝(di)四王(wang)之(zhi)亂。
