東晉庾太后臨朝與外戚庾氏

The Reign of the Empress Dowager Yeu and the Relatives on Emperor Mother's Side of the Yeu Family in the Eastern Tsin Dynasty

東晉明穆庾太后在明帝駕崩、成帝稚幼即位之下，以「皇帝年幼」的合法、正當條件臨朝稱制而攝萬機。儘管庾太后具備接受群臣奏事皆稱「陛下」的至尊皇帝統治威望，然前後長達二年六個月的統治裡，后兄庾亮卻以掌管詔命、宣通內外中書令之職便，配合任法裁物作風和中央州鎮人事的重新安排，發展出外戚政治並一決政事，其政治威勢更達到「朝臣無敢難者」之地步。考察史傳，其與明帝臨崩「升御座」之「庾與馬共天下」承諾暗示和庾太后臨朝政治之形成有緊密之關聯。因此，從權力本質而論，其與歷代外戚政治發展，是一種皇權假藉后妃外家以維繫國祚，而后妃外家依託至尊皇權以專擅朝權的發展無異。所以，司馬皇權在庾太后臨朝而庾亮專擅朝權之世顯然並不微弱。既是如此，治史者所謂東晉一代「臣強主弱」之立論想必然還須要將階段性發展不同的時間因素一併考慮方為周全！儘管如此，庾亮之外戚政治在以厚植「門戶」勢力的目標努力下，並未如前代外戚一般，隨著庾太后臨朝政治之結束而勢崩瓦解。相反地，成康二世庾亮更將外戚政治擴大轉換成庾氏一族之門戶專政。事實顯示，繼庾亮之後，庾翼、庾冰和庾懌兄弟分居中央與地方權勢之位，而權侔人主達到「庾與馬共天下」之實況。逮穆帝即位，外戚身分喪失之後，乃在內部弱體化與以何充、桓溫為首的諸士族門戶聯合勢力挑戰之下才告退幕。其中自有東晉一代士族門閥政治發展之意義蘊涵其中，然庾氏一族未能完全擺脫外戚政治權力本質與作為江左僑姓「新出門戶」土不厚、根不深和宗族不大的內外問題乃是最重要之關鍵。總之，庾氏起自外戚，實具與前代外戚政治發展相同之權力本質。不過，庾亮卻在東晉門閥政治時代發展影響下，開創出不同於前代外戚政治勤於史治、建立事功等不同之政治內容，而以經營門戶、厚植實力之政治轉型為目標。不過，卻在內部與外部諸多條件制限下，隨著「庾與馬共天下」－－名器相予－－既是「因」又是「果」的興衰迅速發展，吾人可以發現，皇權之伸張強大似乎是扮演著水可載舟亦可覆舟的作用；同時，在東晉門閥政治的時代裡，皇權、外戚與士族門閥三者之間的權力發展亦是因緣糾雜而無法脫離。因此，所謂東晉門閥專擅即無外戚勢力發展的論說實有重新思考之必要。

This article focuses on the relation between the empress dowager Yeu who governed the nation as a regent and the relatives on the emperor mother's side of the Yeu family (庚氏). Yeu Liang (庚亮) and Yeu Family rose and gained political power during the empress dowager Ming-Mu ruled the nation as a regent in the Eastern Tsin Dynasty. This was a result of a promise of r 「Sheng Yuh Tzuoh」(升御座)-means 「the empire would belong to Yeu Family and Sy-Ma Family」(司馬氏)(庚與馬共天下) made by the Emperor Ming who was very close to two families. In addition, the Yeu Family turned into a High Family (門閥) and acted without authorization. They devoted to grow the family political power that was the essence of the High Family Politics (門閥政治). It is worth to study the Politics of the High Family in the Eastern Tsin Dynasty in order to re-evaluate the interpretation that there was no political room for relatives on Emperor mother's side while the High Family controlled the politics in the Eastern Tsin Dynasty.(東晉門閥專擅即無外戚勢力發展)