During Emperor Yangs reign

It was not recorded when Yang Dong was born, except that his elder brother Yang Tan (楊倓) was born in 603 and his younger brother Yang You was born in 605. He was the second of three sons of Yang Zhao, Emperor Yang's son and crown prince. His mother was Yang Zhao's concubine, Consort Liu.

In 606, Yang Zhao died. According to Confucian principles of succession, Yang Dong's younger brother Yang You, would have been considered Yang Zhao's heir and successor, as Yang You was born of Yang Zhao's wife Crown Princess Wei. However, Emperor Yang did not create any son of Yang Zhao crown prince to replace Yang Zhao, but left the matters of succession ambiguous between them and Yang Zhao's younger brother Yang Jian the Prince of Qi. He did, however, create Yang Dong and his brothers imperial princes, and Yang Dong was created the Prince of Yue.

In spring 613, when Emperor Yang launched his second of three campaigns against Goguryeo, he left the eight-year-old Yang Dong nominally in charge of the eastern capital Luoyang, with the official Fan Zigai (樊子蓋) actually responsible. Subsequently, while Emperor Yang was in Goguryeo territory, the general Yang Xuangan rebelled near Luoyang, and Fan defended Luoyang under Yang Dong's command. The general Wei Wensheng (衛文昇), leading the army from the capital Chang'an under Yang You's command, came to Luoyang's aid, and Emperor Yang also abandoned the Goguryeo campaign and sent the generals Yuwen Shu and Lai Hu'er (來護兒) back to the Luoyang region; these Sui generals together defeated Yang Xuangan.

In 616, with most of Sui territory, particularly the northern commanderies, engulfed in agrarian rebellions, Emperor Yang went from Luoyang to Jiangdu (江都, in modern Yangzhou, Jiangsu), leaving Yang Dong in charge of Luoyang assisted by the officials Duan Da (段達), Yuan Wendu (元文都), Wei Jin (韋津), Huangfu Wuyi (皇甫無逸), and Lu Chu (盧楚). The rebel leaders Li Mi and Zhai Rang soon took advantage of Emperor Yang's departure (along with the elite Xiaoguo Army (驍果)), to capture the food storages Luokou Storage (洛口倉) and Huiluo Storage (回洛倉), near Luoyang, causing Luoyang to be down on food supplies. In spring 617, Yang Dong sent the generals Liu Changgong and Pei Renji (裴仁基) against Li Mi and Zhai, but Liu and Pei were defeated. In summer 617, with his forces repeatedly defeated by Li Mi's, Yang Dong sent the official Yuan Shanda (元善達) to Jiangdu to seek aid from Emperor Yang, but Emperor Yang, believing in the prime minister Yu Shiji's assessments that the situation was not as severe as Yuan Shanda was claiming, initially refused to send aid. Pei soon surrendered to Li Mi, making Luoyang's position even more precarious. Emperor Yang finally did order the generals Pang Yu (龐玉) and Huo Shiju (霍世舉) to lead the troops from the Chang'an region to aid Luoyang, and Pang and Huo were able to force Li Mi away from Huiluo, allowing Luoyang to regain some of its food supply, although by fall 617 Li Mi had recaptured Huiluo.

In fall 617, Emperor Yang sent the general Wang Shichong (from Jiangdu) and several generals in other outlying areas to lead their troops to aid Luoyang. Wang was able to stem Li Mi's advances, and the armies stalemated. Meanwhile, the general Li Yuan had rebelled at Taiyuan and soon captured Chang'an, declaring Yang Dong's brother Yang You emperor (as Emperor Gong). In spring 618, Li Yuan sent his sons Li Jiancheng and Li Shimin to lead an army to Luoyang, ostensibly to aid it, but Yang Dong and his officials chose to have no communications at all with Li Jiancheng and Li Shimin. After Li Jiancheng and Li Shimin briefly engaged Li Mi, they considered the idea of attacking Luoyang but did not do so, and instead withdrew to Chang'an.

In late spring 618, Emperor Yang was killed in a coup led by the general Yuwen Huaji, who declared Emperor Yang's nephew Yang Hao the Prince of Qin emperor, and began to lead the Xiaoguo Army on a trek back north. Soon, news of Emperor Yang's death arrived at Chang'an and Luoyang. Li Yuan, in response, had Yang You yield the throne to him, establishing Tang Dynasty as its Emperor Gaozu. The officials at Luoyang declared Yang Dong emperor, and those commanderies still loyal to Sui recognized him as emperor as well.

Reign

When describing Yang Dong's brief reign, the official histories indicated that Yang Dong had a handsome face, and was meek, loving, and solemn in his personality.

Yang Dong posthumously honored his father Yang Zhao as an emperor, and honored his mother Consort Liu as empress dowager. The government was led by a collective leadership of seven officials—Duan Da (whom Yang Dong created the Duke of Chen), Wang Shichong (Duke of Zheng), Yuan Wendu (Duke of Lu), Huangfu Wuyi (Duke of Qi), Lu Chu, Guo Wenyi (郭文懿), and Zhao Changwen. They became known as the "seven nobles."

Meanwhile, the officials at Luoyang, fearful that Yuwen Huaji was approaching Luoyang, contemplated their options. Yuan and Lu, under suggestion from Gai Cong (蓋琮), decided to try to make peace with Li Mi by bestowing official Sui honors—including creating him the Duke of Wei, a title that Li Mi himself had claimed. Li Mi, who was apprehensive of Yuwen's advances himself, accepted. For the next month, Li Mi and Yuwen battled, and each time Li Mi was victorious over Yuwen, he would report to Yang Dong. The officials at Luoyang were pleased, except for Wang, who remarked that Yuan and Lu were awarding honors on a bandit, drawing suspicions from Yuan and Lu that Wang was intending to surrender the city to Yuwen. The "seven nobles" thereafter became to suspect each other.

Wang began to incite his troops by telling them that they would soon fall into Li Mi's trap, and that if Li Mi received the command over them (as Li Mi was nominally bestowed the office of supreme commander of the armed forces), he would surely slaughter them for having resisted him. When Yuan received news that Wang was doing this, he planned to ambush Wang. However, Duan revealed the plot to Wang, and Wang started a coup himself first, killing Lu and surrounding the palace. Huangfu fled to Chang'an (controlled by the Tang). At Wang's insistence, Yang Dong surrendered Yuan, who remarked to Yang Dong, "If I die in the morning, Your Imperial Majesty will die in the evening." Yang Dong wept, but still sent Yuan to Wang, who executed Yuan. Wang then met Yang Dong and pledged his loyalty, swearing that all he intended was to save himself and save the empire. Yang Dong took Wang inside the palace to meet Empress Dowager Liu, and Wang swore before her as well. Nevertheless, from this point, all power was in Wang's hands, and Yang Dong himself was powerless.

Upon hearing of Yuan and Lu's deaths, Li Mi broke off the peaceful relations with Yang Dong's regime, now under Wang's control. However, he had a low opinion of Wang, so he did not take much precaution against an attack from Wang. In fall 618, Wang made an all-out attack against Li Mi, dealing Li Mi a crushing defeat at the Battle of Yanshi. Li briefly considered fleeing to his general Xu Shiji, but ultimately decided to head west to Chang'an, to surrender to Tang. Most of Li Mi's former territory (modern central and eastern Henan) surrendered to Wang, and around the same time, the rebel generals Du Fuwei (who controlled modern central and southern Anhui), Shen Faxing (who controlled modern Zhejiang), Zhu Can (whose army roamed in southern Henan), and Dou Jiande (who controlled modern Hebei), all nominally submitted to Yang Dong, and at least in appearance, it appeared that Sui power was becoming restored under Yang Dong.

Meanwhile, Wang was becoming arrogant in his relations with Yang Dong and Empress Dowager Wang. Once, after attending a feast in the palace, he became afflicted with food poisoning, and he became convinced that there was poison in his food, and from that point on refused to see Yang Dong any more. Yang Dong knew that Wang was intent on usurping the throne, but could not think of anything to do other than to try to receive divine favor by donating palace silk to the poor—an action that Wang soon put a stop to by surrounding the palace. By spring 619, Wang had Yang Dong make him the Prince of Zheng and bestow on him the nine bestowments – the ultimate steps before taking the throne. In summer 619, Wang had Duan and Yun Dingxing (雲定興) enter the palace to try to persuade Yang Dong to yield the throne, but Yang Dong refused. Wang then sent a messenger to Yang Dong, promising that although he was taking the throne, he would return the throne to Yang Dong once Yang Dong grew older. He thereafter issued an edict in Yang Dong's name, yielding the throne to himself, ending Sui. Wang took the throne as the emperor of a new state of Zheng.

After reign

Wang Shichong made Yang Dong the Duke of Lu. A month later, Pei Renji and his son Pei Xingyan (裴行儼), as well as the officials Yuwen Rutong (宇文儒童), Yuwen Wen (宇文溫, Yuwen Rutong's brother), and Cui Deben (崔德本) plotted to kill Wang and restore Yang Dong. The news leaked, and the conspirators were slaughtered, along with their families.

Wang Shichong's brother Wang Shiyun (王世惲) the Prince of Qi persuaded Wang Shichong that in order to avoid a repeat of the plot, he needed to put Yang Dong to death. Wang Shichong agreed, and he sent his nephew Wang Renze (王仁則) the Prince of Tang and his servant Liang Bainian (梁百年) to force Yang Dong to drink poison. Yang Dong made one last plea, pointing out that Wang Shichong had previously promised to keep him alive. Liang considered requesting confirmation from Wang Shichong, but Wang Shiyun refused. Yang Dong set sacrifices to Buddha and prayed, "May it be that I will no longer again be reborn into an imperial household." He drank poison, but initially did not die. Wang Shiyun ordered that he be strangled. Wang Shichong posthumously honored Yang Dong as "Emperor Gong", the same posthumous name that Tang later gave Yang Dong's brother Yang You, but as Sui's official history, the Book of Sui was written during Tang, Yang You was recognized as Emperor Gong, while Yang Dong's status as a Sui emperor became ambiguous in traditional histories.

Notes and references

• Book of Sui,vol. 59.

• History of Northern Dynasties, vol. 71.

• Zizhi Tongjian, vols. 180, 182, 183, 184, 185, 186, 187.

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煬帝年間

史書沒有記載楊侗出生的時間，僅知其異母兄楊倓和嫡弟楊侑分別生于603年和605年。

楊侗儀表俊美，眉目如畫，秉性寬厚。大業二年（606年）七月，楊昭去世。八月，煬帝封楊昭三子為王而沒有重新立儲：楊倓為燕王，楊侗為越王，楊侑為代王。煬帝出巡時，常讓楊侗駐守東都洛陽，如大業九年（613年）三月其第二次征討高句麗時，由民部尚書樊子蓋輔佐。期間，禮部尚書楊玄感在洛陽附近起兵作亂，以河內郡主簿唐禕為懷州刺史。唐禕沒有響應，卻告訴了楊侗和樊子蓋，楊侗指揮樊子蓋守御洛陽，守住臨清關令楊玄感不得過境。留守都城長安的楊侑派刑部尚書衛文升率軍四萬來助戰，煬帝也放棄征討高句麗，派左翊衛大將軍宇文述和右驍衛大將軍來護兒回救洛陽。眾隋軍聯合鎮壓了楊玄感之亂。楊侗在高陽朝見煬帝，拜高陽太守。

大業十二年（616年），華北陷入民變，七月，隋煬帝巡幸江都，留楊侗以本官鎮守洛陽，由光祿大夫段達、太府卿元文都、檢校民部尚書韋津、右武衛將軍皇甫無逸和右司郎盧楚輔佐。瓦崗寨民變首領李密、翟讓趁機攻打洛陽，奪取洛陽附近洛口倉和回洛倉的糧食，導致洛陽糧食短缺。十三年（617年）二月，楊侗派虎賁郎將劉長恭、光祿少卿房崱率步騎二萬五千禦敵，劉長恭派河南討捕使裴仁基自汜水西入掩襲敵後，被李密、翟讓得知，隋軍戰敗，死者十分之五六。楊侗赦免劉長恭等並好言撫慰。四月，裴仁基投降李密，洛陽局勢愈發嚴峻。楊侗因屢戰屢敗，派太常丞元善達求援于煬帝，稱洛陽被李密百萬大軍包圍且沒有糧食，再不救就淪陷了。煬帝動容，但內史侍郎虞世基說楊侗被元善達欺騙，洛陽局勢並不像元善達所說，煬帝因此大怒，不僅沒有救援，還派元善達去民變軍占區催糧致其被殺。五月，煬帝派監門將軍龐玉和虎賁郎將霍世舉從長安出兵救援，楊侗命段達、龐玉趁夜出兵，大敗李密，收複回洛倉，洛陽因而恢復了一些補給，但六月回洛倉再被李密所奪。

九月，煬帝又從江都派江都通守王世充率江、淮勁卒，將軍王士隆率邛黃蠻，與河北大使太常少卿韋霽、河南大使虎牙郎將王辯會合河內通守孟善誼、河陽郡尉獨孤武都等各率所部同赴洛陽討伐李密。只有王士隆沒有及時趕到。楊侗命劉長恭等率留守兵，龐玉等率偃師兵，與王世充等合兵十餘萬眾，與李密在洛口交戰，夾洛水對峙。王世充兵敗，堅壁不出，楊侗遣使慰勞，王世充慚懼，請求出戰李密，又敗。同月，太原留守李淵起兵殺入長安，擁立楊侑為隋恭帝。十二月，因王世充屢戰不勝，楊侗遣使慰勞，王世充自稱兵少，數戰後疲弊，楊侗給他增兵七萬。大業十四年（618年）正月，王世充再敗，王辯、孟善誼、其他虎賁郎將楊威、劉長恭、梁德重、董智通、霍世舉等都陣亡，獨孤武都投降，韋津被俘。王世充獨自與數千人逃到河陽，自己下獄請罪，楊侗遣使赦免，召回東都，賜金帛、美女以安其心。李淵派二子唐世子李建成和秦公李世民為左右元帥，率軍進軍洛陽，聲言救援，四月趕到洛陽。楊侗不予理會，李建成和李世民在與李密小有交戰後想進攻洛陽，但最終沒有進攻，撤回長安。朝議郎段世弘等圖謀響應李建成，因李建成撤軍，又私通李密，想放李密軍入城，事洩，楊侗命王世充討伐誅殺。

618年4月11日，宇文述子右屯衛將軍宇文化及弒隋煬帝，殺楊倓、來護兒，而擁立秦王楊浩，率驍果軍北還。煬帝死訊傳到長安和洛陽，李淵迫使隋恭帝禪位，建立唐朝，史稱唐高祖。五月二十四戊辰日（618年6月22日），王世充與元文都、盧楚等率洛陽官員擁立楊侗為皇帝，年號皇泰，仍然忠于隋朝的郡縣也認可楊侗為皇帝。

統治

楊侗大赦天下，追封煬帝為世祖明皇帝，楊昭為世宗孝成皇帝，尊母小劉良娣為皇太后；以王世充為納言、左翊衛大將軍、攝吏部尚書，封鄭國公，以段達為開府儀同三司兼納言、右翊衛大將軍、攝禮部尚書，封陳國公，元文都為內史令，封魯國公，皇甫無逸為兵部尚書、右武衛大將軍，封杞國公，郭文懿為內史侍郎、趙長文為黃門侍郎、盧楚為內史令，七人共同輔政，時人號稱「七貴」。

六月，宇文化及率大軍北上接近洛陽，一路官員都投降，洛陽官員擔心。蓋琮上疏建議聯合李密。元文都對盧楚說可以赦免李密，令其討伐宇文化及，待宇文化及兵敗，李密也疲憊了，也可擊破擒獲。于是以蓋琮為通直散騎常侍，與馬公政為使者帶著敕書招撫李密。李密與宇文化及對峙，也害怕宇文化及的勢力，見到蓋琮大喜，派元帥府記室參軍李儉、上開府徐師譽等為使者向楊侗投降，解送所俘虜的宇文化及手下雄武郎將于洪建。楊侗大悅，于左掖門外酷刑處決于洪建，厚待使者，以李儉為司農卿，徐師譽為尚書右丞，冊拜李密為太尉、尚書令、東南道大行台行軍元帥、魏國公，命他討伐宇文化及，然後入朝輔政；以李密部將徐世勣為右武候大將軍，下詔稱李密忠誠。王世充不贊同招撫李密，因此與元文都等不和。七月，楊侗遣大理卿張權、鴻臚卿崔善福賜李密詔書，李密受詔。李密每次交戰取勝，都奏報楊侗。當月，元文都欲暗殺王世充，卻被段達出賣，王世充發動兵變。元文都奉楊侗御乾陽殿，命諸將閉門拒守。王世充攻入太陽門，皇甫無逸、龐玉出逃。王世充殺死盧楚，攻紫微宮門。楊侗派人登上紫微觀責問其用心，王世充稱被元文都和盧楚謀害，請求殺元文都。段達命押元文都出門，元文都對楊侗說：「臣今朝死，陛下夕及矣」，楊侗亦哭。王世充殺元文都，又殺元文都、盧楚的兒子們。段達以楊侗名義命開門放王世充軍入宮。王世充派人替換所有的宿衛，再進入乾陽殿面聖。楊侗責怪王世充擅自殺大臣，王世充哭著發誓稱是為了自保和拯救社稷，楊侗以為他確是誠心，令他升殿，說了很久的話，再帶他入宮見劉太后，王世充又對劉太后表忠，披髮盟誓自己沒有二心。王世充被任為左僕射、總督內外諸軍事，又捕殺趙長文、郭文懿，從此大權歸于王世充，楊侗沒有權力，不悅，與記室陸士季謀害王世充未果。

先前楊侗的國子祭酒徐文遠被李密俘虜。李密得知元文都等人被殺，聽從徐文遠建議，與王世充控制的隋朝決裂。八月，宇文化及所任歷陽太守杜伏威上表楊侗，被拜為東道大總管，封楚王；自稱江南道大總管沈法興亦上表楊侗，自稱大司馬、錄尚書事、天門公。

九月，李密因為輕敵在偃師之戰為王世充所敗而投靠李淵建立的唐朝。李密的領地多歸順王世充。郇王楊慶先前投降李密，改姓郭，此時回到洛陽又改回姓楊，楊侗不責怪，還拜他為宗正卿。楚帝朱粲遣使投降隋朝，被楊侗封為楚王。宇文化及殺楊浩，楊侗成為唯一在位的隋朝皇帝。十月，王世充收李密美人珍寶及將卒十餘萬人回洛陽獻俘，楊侗大赦，以王世充為太尉、尚書令，內外諸軍事，開太尉府。十二月，被唐軍圍攻的隋河東守將堯君素製作木鵝，將寫有形勢的表文系在其頸上，沿河放下，由河陽守軍送到洛陽，楊侗見後嘆息，拜堯君素金紫光祿大夫。

王世充起初擔心人心不服，還討好楊侗，禮數尚且謙虛恭敬；後來漸漸驕橫。一次他入宮接受賜飯，回去後嘔吐，懷疑自己的食物被投毒，從此拒絕入朝面聖。皇泰二年（619年）正月，楊侗知道王世充想篡位，卻只能讓僧人布施宮中絲綢、珍寶給窮人以求神佛庇佑。王世充派黨羽張績、董浚守章善、顯福二門，不許宮中雜物出門。

閏正月，夏國主竇建德與王世充結好，遣使奉表于楊侗，受封為夏王。

三月，王世充仗著擊破李密的威望，派段達等迫使楊侗加他九錫，楊侗推託王世充擊破李密以來沒有大功，等天下再平定一些再議，段達說這是王世充想要的，楊侗看了他很久以後只能作罷。段達等人以楊侗詔書名義命王世充為相國，假黃鉞，總百揆，進爵鄭王，加九錫，備法物，鄭國置丞相以下官。段達又以楊侗名義加王世充殊禮。四月初五癸卯日（619年5月23日），王世充派段達和雲定興等十人說服楊侗禪位，楊侗斂膝據案，大怒拒絕，說這是隋高祖的天下和隋世祖的東都，指責對方身為隋朝舊臣卻口出此言，神色凜然，侍衛莫不流汗。退朝後，楊侗對著劉太后哭。王世充又派使者說服楊侗，說天下未定需要年長君主，發誓等天下太平、楊侗長大就把皇位還給他，派兄王世惲囚禁楊侗於含涼殿，三次上表辭讓及下禪位敕書都不令楊侗得知。兩天後，王世充自稱皇帝，建立鄭朝，改元開明。

退位後

王世充改封楊侗為潞國公，食邑五千戶。楊侗每日只能焚香禮佛以祈求平安。五月，尚書左丞宇文儒童、尚食直長宇文溫兄弟、尚食直長陳謙、禮部尚書裴仁基、左輔大將軍裴行儼父子、散騎常侍崔德本策劃攻殺王世充黨羽，複立楊侗。事情敗露，王世充滅他們三族。

齊王王世惲說這些人謀反是因為楊侗還在，勸王世充殺死楊侗以絕後患。六月，王世充派侄子王仁則和家僕梁百年攜鴆酒去楊侗處，對他說：「願皇帝飲此酒。」楊侗指出這不符合太尉（即王世充）先前的誓言，梁百年想轉達王世充，被王世惲拒絕。楊侗自知難逃一死，請求見母親道別，不獲准，于是布下蓆子焚香向佛像祈禱：「願生生世世不要再生在帝王尊貴之家」，遂仰藥；但一時半刻竟沒毒發，最後被縊死，謚號恭皇帝。

評價

• 《北史》論曰：至令趙及燕、越，皆不得死，悲夫！

• 《隋書》史臣曰：至令趙及燕、越皆不得其死，悲夫！