疾病與邊疆——以北宋越南戰爭（981—1076）為例

Abstract

本文的主旨在探究疾病與戰爭、邊疆的關係，以第十至十一世紀之間北宋與交趾的戰爭為例。 筆者首先討論十世紀交趾自立後的政治與軍事發展，過去學界多以宋代為中心觀看交趾，而本文則立足於交趾的視角，探究交趾侵宋的立場與理由。交趾以紅河流域為核心，向南北兩方展開軍事行動，藉由親征與鎮壓手段鞏固內部統治並展示王權威信。南方的占城為其主要對手，雙方爆發多次戰爭，交趾多次勝出並強迫占城朝貢，實踐以模仿中國天下體制為藍本的區域秩序觀。在面對北宋時，交趾除劫掠邊境與索還逃民外，亦透過武力試探與蠶食領土，展現其擴張性格。這種擴張背後有賴於其改造自中原的天下觀，主張南北平等與天命授權，並透過歷史神話建構國家正統性。交趾並不將北宋視為不可挑戰的宗主國，而是將之視為平起平坐的對手，在文化與政治上積極塑造自己的國家地位。 其次，本文聚焦於宋代及其以前的南方印象，以文人創作與醫學文本作為考察的對象。自東漢以來，瘴癘成為南方的代表性符號，歷代文人將其視為疾病與死亡的象徵，唐代更將瘴與氣候、蠻族連結，擴展其文化意涵。宋代士人繼承前人對南方的畏懼，並加入自身觀察與醫療知識。宋儒不僅延續瘴的書寫傳統，也嘗試將其用於政治隱喻。另外，宋代醫者在理論與實踐上取得進展，普遍以陰陽氣失調解釋病因，並積極探索治療方式。面對嶺南之惡，人們普遍選擇逃避，僅有謫官試圖適應。儘管政府推動醫療改革並打擊巫術，南方醫療資源仍匱乏，改革效果有限。此一南方與疾病連結的刻板印象，在交趾與北宋的外交與戰爭上扮扮演重要角色。 最後，本文聚焦戰爭與疾病如何影響北宋邊疆政策。交趾戰爭發生於神宗拓邊熱潮之際，但南征過程中爆發的大規模疫病重創宋軍，促使神宗選擇退兵。雖軍事上取得短暫勝利，卻因疾病導致官兵傷亡慘重，使得開發新佔領地的計畫以失敗告終。廣源州的開發案因黃金產量有限、駐軍死傷與交趾持續干預終止。儘管北宋擁有優勢，卻在現實條件與文化觀念的限制下選擇妥協。歷史上根深蒂固的南方印象使得宋廷對南疆態度消極，未能進一步經營，最終以劃界與外交妥協收場，反映疾病與文化觀念在邊疆政治中的深遠影響。

This thesis explores the close relationship between disease, war, and frontiers. I take the Nothern Song Dynasty and Jiaozhi’s military affairs from the tenth to the eleventh centuries as examples. I first examines the political and military developments following the establishment of an independent state in Jiaozhi. Previous academic studies have tended to view Jiaozhi from the perspective of the Song Dynasty, but this article draws on Vietnamese historical sources to highlight Jiaozhi’s position and reasons for invading the Song Dynasty from Jiaozhi's perspective. Centered around the Red River basin, Jiaozhi launched military campaigns in both northern and southern directions, consolidating internal rule and demonstrating the authority of the monarchy through personal campaigns and suppression. Champa in the south was its primary rival, and the two sides engaged in multiple wars, with Jiaozhi emerging victorious on several occasions and forcing Champa to pay tribute, thereby implementing a regional order based on the Chinese imperial system. When facing the Northern Song Dynasty, Jiaozhi not only raided the border and demanded the return of fugitives but also used military force to test and gradually encroach upon territory, demonstrating its expansionist nature. This expansion was underpinned by its adaptation of the Chinese concept of the ‘heavenly realm,’ which advocated equality between the north and south and divine mandate, and sought to establish national legitimacy through historical mythology. Jiaozhi did not regard the Northern Song Dynasty as an unchallengeable suzerain state, but rather as an equal rival, actively shaping its own national status in cultural and political terms. Secondly, this article focuses on impressions of the South during the Song dynasty and earlier periods. Since the Eastern Han Dynasty, zhangli (malaria) had become a representative symbol of the South, with literati throughout the ages viewing it as a symbol of disease and death. During the Tang Dynasty, malaria was further linked to climate and barbarian tribes, expanding its cultural connotations. Song Dynasty scholars inherited their predecessors' fear of the South and added their own observations and medical knowledge. Song Confucian scholars not only continued the tradition of writing about malaria but also attempted to use it as a political metaphor. Additionally, Song Dynasty physicians made progress in theory and practice, generally explaining the causes of disease as imbalances in yin and yang energy and actively exploring treatment methods. Faced with the evils of Lingnan, people generally chose to flee, with only exiled officials attempting to adapt. Despite the government's efforts to reform medical practices and crack down on witchcraft, medical resources in the south remained scarce, and the reforms had limited effect. Finally, this thesis focuses on how war and disease influenced the Northern Song Dynasty's border policies. The Jiaozhi War occurred during Emperor Shenzong's expansionist campaign, but the outbreak of a large-scale epidemic during the southern campaign severely weakened the Song army, prompting Emperor Shenzong to withdraw his troops. Although the military achieved a temporary victory, the heavy casualties among troops due to disease led to the failure of plans to develop the newly occupied territories. The development project in Guangyuan Prefecture was terminated due to limited gold production, military casualties, and continued interference from Jiaozhi. Despite the Northern Song Dynasty's advantages, it chose to compromise under the constraints of practical conditions and cultural beliefs. The deeply ingrained southern perception in history led the Song court to adopt a passive attitude toward the southern frontier, failing to further develop it, and ultimately resolving the issue through border demarcation and diplomatic compromise. This reflects the profound influence of disease and cultural concepts on frontier politics.