西漢成哀朝外戚政治與爭鬥

「外戚政治」是西漢政治文化中相當重要的一環，參與其中者同時包含皇室姻親、家族團體等多重角色。就連今日，只要一提起西漢外戚家族，也必定會想起諸呂、竇氏、霍氏，以及最終篡奪西漢的王氏家族（王莽）。但過往的西漢外戚政治研究多半集中於漢高祖至漢武帝時期，漢武帝時期後則以霍光「一枝獨秀」，至於其他外戚家族，甚至改朝換代的王莽家族，都缺少深入而有系統的研究。王氏家族的興盛遠超西漢諸多外戚，包含漢高祖外家呂氏。班氏在其著作《漢書》中稱該家族：「家凡十侯，五大司馬，外戚莫盛焉」。王氏家族在漢成帝、漢哀帝朝之間興起、發展、壯大，同時因新皇帝外家的威脅而沒落，期間涉及多次家族惡鬥引發的政爭，亦嚴重衝擊西漢後期皇位傳嗣，造成皇權衰弱進而私有化的惡性循環。若將西漢朝廷視作一個政治場域(political Field)，則外戚政治和皇權便是其中相互合作又相互競爭的力量兩端，皇帝和外戚家族又是如何參與其中，改變了西漢的政治發展。

關鍵字

外戚政治；漢成帝；漢哀帝；皇權；王莽

並列摘要

The consort family politic is important to Western Han dynasty not only because the structure of government is based Imperial and its consort kin but also the members of consort usually controlled the politic of the Empire. The most famous Imperial consort family during Western Han dynasty is House of Wang which is also family of Wang Mang who eventually seized the authority from Ping ti. But the researches of the Imperial consort families during Western Han dynasty seldom talk about how the families developed and grew their own strength along with Emperors. Especially House of Wang is way more stronger than any families of the consort, even more stronger then House of Lu, the consort family of Gaozu. Ban left some description about the family in Han shu漢書, “There have totally ten Hóu侯 and five Dah Sima大司馬 come from this family. There is no family more powerful than them.”. Ban kept the record about how the family developed their own politic gang in the government and why the family suddenly fell during the reign of Ai ti. All of the waves caused by or related to House of Wang made whole Empire ups and downs, influenced directly to the throne and dragged the other families into fights between each other. In the end, the authority of Imperial became meaningless but Wang’s tool to rule the Empire.