生平

為晉征戰

西晉中葉爆發八王之亂，對各地造成嚴重破壞之餘亦令劉淵、石勒等內遷的外族趁機起兵。都督幽州諸軍事王浚見天下將亂，就與段務勿塵領導的段部鮮卑合作，引以為援。王浚後又表務勿塵為親晉王，至太安二年（303年）又務勿塵又得王浚表封為遼西公。晉懷帝在位期間，段務勿塵獲授大單于，以段匹磾任左賢王，率眾協助晉軍出討，假授撫軍大將軍。

永嘉六年（312年），王浚命督護王昌等人領軍聯同務勿塵世子段疾陸眷及段匹磾、段文鴦、段末柸等共攻石勒根據地襄國。石勒屢遭擊敗，但卻成功乘著段部鬆懈的機會生擒段末柸，但石勒厚待末柸並以此請和，最終疾陸眷得以二百五十匹鎧馬及金銀各一簏贖還末柸，並退軍。王昌在失去段部兵力下亦無力繼續進攻，亦得撤退。段務勿塵去世後，段疾陸眷繼襲段部及遼西公爵位，因著對石勒釋放段末柸的感恩，遼西國不再支持王浚，最終王浚於建興二年（314年）為石勒所滅。

據守幽州

王浚覆滅，幽州刺史由段匹磾所領。而石勒在滅王浚後所置的幽州刺史劉翰不久就以薊城叛歸段匹磾，段匹磾遂以薊為根據地繼續對抗石勒。建興四年（316年），司空、并州刺史劉琨失并州，遂應段匹磾邀請率眾至薊，與段匹磾結盟。建武元年（317年），劉琨與段匹磾同討石勒，匹磾推劉琨為大都督，移檄四方請段部鮮卑出兵與他們於襄國集合。石勒對此恐懼，於是出重金賄賂段末柸，而段末柸一直都很感激石勒早前厚待並釋放他的行為，於是離間段疾陸眷及段匹磾叔父段涉複辰與段匹磾的關係：「以父兄而從子弟邪？雖一旦有功，匹獨收之矣。」二人聽信，故段部沒有派兵前去。失去段部支持，劉琨及匹磾勢弱，無力繼續進攻，只好退兵。

太興元年（318年），段疾陸眷去世，因兒子年幼而由叔父段涉複辰襲位，段匹磾亦回遼西國奔兄長之喪。不過，段末柸竟然向段涉複辰誣稱段匹磾要前來奪位，匹磾走到右北平時就遭段末柸率軍擊敗，只好逃返薊城。當時劉琨派兒子劉群隨匹磾奔喪，就遭段末柸俘虜，末柸又圖離間劉琨及匹磾，不但厚禮劉群，又讓劉群寫信給劉琨，表達他願以劉琨為幽州刺史，請其與己結盟共攻匹磾的意願。信件遭段匹磾巡邏騎兵截獲，匹磾向來敬重劉琨，故仍沒有加害劉琨之意，還特地將信件展示給全不知情的劉琨知道，劉琨亦表示不會因為兒子而背叛他。不過匹磾弟段叔軍卻對匹磾說：「吾胡夷耳，所以能服晉人者，畏吾眾也。今我骨肉構禍，是其良圖之日，若有奉琨而起，吾族盡矣。」匹磾聽後改變主意，將劉琨拘留了。劉琨被拘令遠近都憤恨慨嘆，劉琨庶長子劉遵與劉琨左長史楊橋及并州治中如綏；以及雁門太守王據、後將軍韓據、代郡太守闢閭嵩先後因而圖襲匹磾，都被匹磾平定。有野心的東晉大將軍王敦秘密派人命段匹磾殺掉劉琨，匹磾亦怕群眾以劉琨反抗自己，最終就假稱有詔命而縊殺劉琨。可是，段匹磾殺害劉琨的行為不但沒令群眾安定下來，反而令劉琨部眾及屬官和歸附的人們都離散，分別投於段末柸的遼西國及石勒，反削弱了段匹磾的勢力。

隕身全節

最終段匹磾無力繼續守住幽州地盤，只好轉依據守厭次的邵續。太興三年（320年），段末柸主動攻段匹磾，匹磾戰敗受傷，遂與邵續聯手共追末柸作反擊，成功擊敗末柸。匹磾接著就與文鴦直擊薊城。但石勒乘段匹磾等北進的機會派兵圍攻厭次，邵續出城迎擊被俘。段匹磾等軍回城時在城八十里得知邵續被俘，部眾驚懼潰散，更遭圍城的石虎乘虛進襲，只因段文鴦奪勇抵抗才得以回城繼續拒守。厭次繼續遭到圍困，段文鴦見石虎抄掠城下，打算出城進擊，但匹磾不允許，文鴦於是帶了數十騎出擊，奮勇作戰至力竭被擒。驍勇的段文鴦被俘令城內人心恐懼，厭次守到太興四年（321年）亦再守不住。段匹磾在城陷前打算隻身南奔東晉，但為樂安內史邵洎以兵阻止，邵洎更想將東晉朝廷派來的使者王英押送給石虎，段匹磾就嚴肅地指責他：「卿不能遵兄之志，逼吾不得歸朝，亦以甚矣，復欲執天子使者，我雖胡夷，所未聞也。」最終還是讓王英南走。城陷時，段匹磾穿著晉朝朝服，手持符節出降。被送到襄國後獲石勒署為冠軍將軍。但段匹磾在那不對石勒行禮，常常穿著晉朝朝服及拿著晉朝符節。後來有人圖謀推段匹磾為主起事，事敗，匹磾亦被殺。

延伸閱讀

Early life and career

Duan Pidi was a member of the Xianbei Duan clan of Liaoxi. His father, Duan Wuwuchen was the head of the clan between 303 and 311. At the start of the 4th century, the Duan clan allied with the Youzhou warlord, Wang Jun and played an important role in Wang's campaign against the Prince of Chengdu, Sima Ying, during the War of the Eight Princes. The Duan tribe and Wang Jun continued their association after the war, combining their efforts to stop the new and growing state of Han-Zhao. Some time around 310, Pidi's elder brother, Duan Jilujuan, succeeded Wuwuchen as chieftain following his death.

Duan Pidi participated during Jilujuan's attack on Xiangguo in 312, as part of Wang Jun's plan to divert the Han general, Shi Le, away from the rebelling city of Yuanxiang (苑鄕, in present-day Hebei and Beijing). The Duan forces fought Shi Le at Xiangguo but their star general, Pidi's cousin, Duan Mopei, was captured in battle. Despite being a prisoner, Mopei was treated with courtesy by Shi Le, which pleased Jilujuan. Because of this, the Duan tribe ceased their enmity with Shi Le and distanced themselves from Wang Jun.

Wang Jun was eventually captured and executed by Shi Le in 314. After Wang's defeat, Shi Le appointed a man named Liu Han (劉翰) to be acting Inspector of Youzhou based in Jicheng. However, Liu Han instead fled to Duan Pidi, who he offered control over Jicheng. Pidi accepted on his own accord before occupying the city and submitting himself to Sima Rui, the paramount leader of Jin in the south. For this, Sima Rui made Pidi Jin's new Inspector of Youzhou. Pidi also urged Shi Le's Administrator of Leling, Shao Xu, to submit to the Jin prince as well. Shao Xu did so, and Shi Le immediately responded by sending his army to besiege him. However, Pidi sent Duan Wenyang to reinforce Shao Xu, so Shi Le called off his attack.

As Inspector of Youzhou

Alliance with Liu Kun

In 316, Shi Le sent his nephew Shi Hu to attack the Administrator of Wei Commandery, Liu Yan (劉演). Pidi sent Wenyang to rescue Liu Yan, and while the commandery fell, Liu Yan was safely retrieved. Later that year, the Inspector of Bingzhou, Liu Kun lost his province to Shi Le. Liu Kun was left with nowhere to go, so Pidi sent a letter to invite him over to his base. Liu Kun took what was left of his army to meet with Pidi and the two men quickly befriended each other. Forming a brotherly bond, Pidi and Liu Kun arranged their relatives to marry one another to further cement their friendship.

The next year, Pidi and Liu Kun swore an oath of alliance by smearing their lips with blood. Afterwards, they sent their respective envoys to deliver a joint petition urging Sima Rui to claim the imperial title. Liu Kun chose his nephew Wen Jiao to deliver the petition, while Pidi chose his Chief Clerk of the Left, Rong Shao (榮卲). After their envoys reached the southern capital, Pidi proclaimed Liu Kun as Grand Commander. He also later tried to get Jilujuan into joining forces with him in a campaign against Shi Le. However, Duan Mopei advised Jilujuan against agreeing with Pidi, so Jilujuan did not respond, and Pidi had to cancel the campaign.

Arrest and execution of Liu Kun

Jilujuan died in early 318 and was succeeded by his uncle, Duan Shefuchen. Pidi left Jicheng to attend his funeral but without his knowledge, Duan Mopei manipulated Shefuchen into believing that Pidi was about to usurp his power. At Zuobeiping, Shefuchen attacked Pidi but was then betrayed by Mopei who assassinated him while his and Pidi's forces were fighting. Mopei then took command of the assault and routed Pidi. During this, Mopei capturing Liu Kun's son Liu Qun (劉群), who was escorting Pidi to the funeral.

Mopei treated Liu Qun well and considered supporting Liu Kun into becoming the new Inspector of Youzhou. He had Liu Qun write a letter to his father asking him to work as an agent within Pidi's camp, but his envoy was caught by Pidi's scouts along the way. Liu Kun knew nothing of the letter when Pidi confronted him with it. Pidi had no suspicion towards Liu Kun, and Liu Kun himself assured that he had no intentions to betray Pidi. Pidi let him off at first, but his younger brother, Duan Shujun (段叔軍), was able to get his brother to heavily reconsider his actions.

Pidi quickly had Liu Kun arrested. Liu Kun's son, Liu Zun (劉遵), upon hearing his father's arrest, mounted a defence in his camp but was defeated by Pidi. Two of Liu Kun's generals, Pilü Song (辟閭嵩) and Han Ju (韓據), also planned to retaliate, but Pidi had the conspirators executed after their plot leaked. On 22 June, through the consent of Sima Rui's commander, Wang Dun, Pidi claimed that he had received an imperial edict to arrest Liu Kun and subsequently executed him along with his four sons and nephews via strangulation.

Although Liu Kun had long helped Jin in attempting to restore its authority in the north, Sima Rui refused to punish Pidi and forbid anyone from mourning Liu Kun, as Rui and most of the court thought of Pidi as a powerful and valuable asset. Despite Sima Rui's leniency, Pidi had underestimated Liu Kun's popularity, and the breaking of his oath caused many of the Han Chinese and tribal people to lose their trust in Pidi.

Alliance with Shao Xu

Fleeing to Shao Xu

Seeing that support for Pidi was declining, Duan Mopei took the opportunity to attack him. Pidi led his army away from battle and tried to flee to Shao Xu in Leling but was badly routed by Shi Le's general Shi Yue (石越; not to be confused with the Former Qin general of the same name, Shi Yue) at Mount Yan. Pidi retreated back to Jicheng while Mopei declared himself the new Inspector of Youzhou. Pidi remained in his city for a year, but by 319, his situation had worsened. Shi Le's general Kong Chang had taken all of Youzhou's commanderies while most of Pidi's soldiers abandoned him due to depleting rations. Pidi planned to escape through Shanggu but the Prince of Dai, Tuoba Yulü, was waiting to attack him there. Desperate, Pidi abandoned his wife and children and made another attempt to flee to Shao Xu, this time successfully doing so.

Defense of Yanci

In 320, Pidi's army was once again harassed by Mopei. Pidi pleaded to Shao Xu to assist him in getting revenge on Mopei, so the two men headed out and routed Mopei. Pidi followed up his victory by attacking Jicheng together with Duan Wenyang to reclaim his old base. This proved a fatal mistake as Shao Xu was left exposed to Shi Le. Shi Hu attacked Yanci (厭次, around present-day Dezhou, Shandong) and captured Shao Xu. News of Shao Xu's defeat reached Pidi, causing him to rush back to save the city. Duan Wenyang helped the army fight their way back into the city, where Pidi commanded the defence together with Shao Xu's family. In the middle of the year, Wenyang defeated Kong Chang, but it was not enough to completely repel the Zhao army.

Fighting continued into the next year in 321. Shi Hu attacked Pidi at Yanci again, while Kong Chang occupied the inner cities. Duan Wenyang volunteered himself to lead a daring charge with his cavalries to drive back the invaders. Wenyang valiantly fought and killed dozens of Shi Hu's soldiers. Supposedly, even after his horse had collapsed, Wenyang fought back with his spear, and when his spear snapped, he fought with his blade. This lasted for a day but Wenyang was eventually captured Shi Hu. His capture lowered the morale of the city's defenders.

Defeat and death

Faced with imminent defeat, Pidi planned to flee alone to the south to serve Sima Rui. However, Shao Xu's brother, Shao Ji (邵樂) detained him and handed over Sima Rui's envoy, Wang Ying (王英) to Shi Hu. Shortly after, Shao Ji and his sons bound themselves to coffins and went out to surrender. When Pidi met with Shi Hu, he said to him, "I have received the favor of Jin, and my ambition was to destroy you. It is unfortunate that things have come to this, but I cannot respect you." Shi Le and Shi Hu had always respected Pidi, so much so that after his capture, Shi Hu lifted him up in the air and had him saluted as a gesture of companionship. Pidi was made Champion General, while Wenyang was made General of the Household Gentlemen of the Left.

Despite Shi Le's favour, Pidi remained loyal to Jin. Pidi often dressed himself in clothing used in the Jin court and held the imperial staff of authority that Sima Rui gave him. Shi Le was worried that Pidi's attitude foreboded a future revolt. After some time, Shi Le had Pidi put to death along with Wenyang and Shao Xu.