炀帝年间

史书没有记载杨侗出生的时间，仅知其异母兄杨倓和嫡弟杨侑分别生于603年和605年。

杨侗仪表俊美，眉目如画，秉性宽厚。大业二年（606年）七月，杨昭去世。八月，炀帝封杨昭三子为王而没有重新立储：杨倓为燕王，杨侗为越王，杨侑为代王。炀帝出巡时，常让杨侗驻守东都洛阳，如大业九年（613年）三月其第二次征讨高句丽时，由民部尚书樊子盖辅佐。期间，礼部尚书杨玄感在洛阳附近起兵作乱，以河内郡主簿唐禕为怀州刺史。唐禕没有响应，却告诉了杨侗和樊子盖，杨侗指挥樊子盖守御洛阳，守住临清关令杨玄感不得过境。留守都城长安的杨侑派刑部尚书卫文升率军四万来助战，炀帝也放弃征讨高句丽，派左翊卫大将军宇文述和右骁卫大将军来护儿回救洛阳。众隋军联合镇压了杨玄感之乱。杨侗在高阳朝见炀帝，拜高阳太守。

大业十二年（616年），华北陷入民变，七月，隋炀帝巡幸江都，留杨侗以本官镇守洛阳，由光禄大夫段达、太府卿元文都、检校民部尚书韦津、右武卫将军皇甫无逸和右司郎卢楚辅佐。瓦岗寨民变首领李密、翟让趁机攻打洛阳，夺取洛阳附近洛口仓和回洛仓的粮食，导致洛阳粮食短缺。十三年（617年）二月，杨侗派虎贲郎将刘长恭、光禄少卿房崱率步骑二万五千御敌，刘长恭派河南讨捕使裴仁基自汜水西入掩袭敌后，被李密、翟让得知，隋军战败，死者十分之五六。杨侗赦免刘长恭等并好言抚慰。四月，裴仁基投降李密，洛阳局势愈发严峻。杨侗因屡战屡败，派太常丞元善达求援于炀帝，称洛阳被李密百万大军包围且没有粮食，再不救就沦陷了。炀帝动容，但内史侍郎虞世基说杨侗被元善达欺骗，洛阳局势并不像元善达所说，炀帝因此大怒，不仅没有救援，还派元善达去民变军占区催粮致其被杀。五月，炀帝派监门将军庞玉和虎贲郎将霍世举从长安出兵救援，杨侗命段达、庞玉趁夜出兵，大败李密，收复回洛仓，洛阳因而恢复了一些补给，但六月回洛仓再被李密所夺。

九月，炀帝又从江都派江都通守王世充率江、淮劲卒，将军王士隆率邛黄蛮，与河北大使太常少卿韦霁、河南大使虎牙郎将王辩会合河内通守孟善谊、河阳郡尉独孤武都等各率所部同赴洛阳讨伐李密。只有王士隆没有及时赶到。杨侗命刘长恭等率留守兵，庞玉等率偃师兵，与王世充等合兵十馀万众，与李密在洛口交战，夹洛水对峙。王世充兵败，坚壁不出，杨侗遣使慰劳，王世充惭惧，请求出战李密，又败。同月，太原留守李渊起兵杀入长安，拥立杨侑为隋恭帝。十二月，因王世充屡战不胜，杨侗遣使慰劳，王世充自称兵少，数战后疲弊，杨侗给他增兵七万。大业十四年（618年）正月，王世充再败，王辩、孟善谊、其他虎贲郎将杨威、刘长恭、梁德重、董智通、霍世举等都阵亡，独孤武都投降，韦津被俘。王世充独自与数千人逃到河阳，自己下狱请罪，杨侗遣使赦免，召回东都，赐金帛、美女以安其心。李渊派二子唐世子李建成和秦公李世民为左右元帅，率军进军洛阳，声言救援，四月赶到洛阳。杨侗不予理会，李建成和李世民在与李密小有交战后想进攻洛阳，但最终没有进攻，撤回长安。朝议郎段世弘等图谋响应李建成，因李建成撤军，又私通李密，想放李密军入城，事泄，杨侗命王世充讨伐诛杀。

618年4月11日，宇文述子右屯卫将军宇文化及弑隋炀帝，杀杨倓、来护儿，而拥立秦王杨浩，率骁果军北还。炀帝死讯传到长安和洛阳，李渊迫使隋恭帝禅位，建立唐朝，史称唐高祖。五月二十四戊辰日（618年6月22日），王世充与元文都、卢楚等率洛阳官员拥立杨侗为皇帝，年号皇泰，仍然忠于隋朝的郡县也认可杨侗为皇帝。

统治

杨侗大赦天下，追封炀帝为世祖明皇帝，杨昭为世宗孝成皇帝，尊母小刘良娣为皇太后；以王世充为纳言、左翊卫大将军、摄吏部尚书，封郑国公，以段达为开府仪同三司兼纳言、右翊卫大将军、摄礼部尚书，封陈国公，元文都为内史令，封鲁国公，皇甫无逸为兵部尚书、右武卫大将军，封杞国公，郭文懿为内史侍郎、赵长文为黄门侍郎、卢楚为内史令，七人共同辅政，时人号称「七贵」。

六月，宇文化及率大军北上接近洛阳，一路官员都投降，洛阳官员担心。盖琮上疏建议联合李密。元文都对卢楚说可以赦免李密，令其讨伐宇文化及，待宇文化及兵败，李密也疲惫了，也可击破擒获。于是以盖琮为通直散骑常侍，与马公政为使者带著敕书招抚李密。李密与宇文化及对峙，也害怕宇文化及的势力，见到盖琮大喜，派元帅府记室参军李俭、上开府徐师誉等为使者向杨侗投降，解送所俘虏的宇文化及手下雄武郎将于洪建。杨侗大悦，于左掖门外酷刑处决于洪建，厚待使者，以李俭为司农卿，徐师誉为尚书右丞，册拜李密为太尉、尚书令、东南道大行台行军元帅、魏国公，命他讨伐宇文化及，然后入朝辅政；以李密部将徐世绩为右武候大将军，下诏称李密忠诚。王世充不赞同招抚李密，因此与元文都等不和。七月，杨侗遣大理卿张权、鸿胪卿崔善福赐李密诏书，李密受诏。李密每次交战取胜，都奏报杨侗。当月，元文都欲暗杀王世充，却被段达出卖，王世充发动兵变。元文都奉杨侗御乾阳殿，命诸将闭门拒守。王世充攻入太阳门，皇甫无逸、庞玉出逃。王世充杀死卢楚，攻紫微宫门。杨侗派人登上紫微观责问其用心，王世充称被元文都和卢楚谋害，请求杀元文都。段达命押元文都出门，元文都对杨侗说：「臣今朝死，陛下夕及矣」，杨侗亦哭。王世充杀元文都，又杀元文都、卢楚的儿子们。段达以杨侗名义命开门放王世充军入宫。王世充派人替换所有的宿卫，再进入乾阳殿面圣。杨侗责怪王世充擅自杀大臣，王世充哭著发誓称是为了自保和拯救社稷，杨侗以为他确是诚心，令他升殿，说了很久的话，再带他入宫见刘太后，王世充又对刘太后表忠，披发盟誓自己没有二心。王世充被任为左仆射、总督内外诸军事，又捕杀赵长文、郭文懿，从此大权归于王世充，杨侗没有权力，不悦，与记室陆士季谋害王世充未果。

先前杨侗的国子祭酒徐文远被李密俘虏。李密得知元文都等人被杀，听从徐文远建议，与王世充控制的隋朝决裂。八月，宇文化及所任历阳太守杜伏威上表杨侗，被拜为东道大总管，封楚王；自称江南道大总管沈法兴亦上表杨侗，自称大司马、录尚书事、天门公。

九月，李密因为轻敌在偃师之战为王世充所败而投靠李渊建立的唐朝。李密的领地多归顺王世充。郇王杨庆先前投降李密，改姓郭，此时回到洛阳又改回姓杨，杨侗不责怪，还拜他为宗正卿。楚帝朱粲遣使投降隋朝，被杨侗封为楚王。宇文化及杀杨浩，杨侗成为唯一在位的隋朝皇帝。十月，王世充收李密美人珍宝及将卒十馀万人回洛阳献俘，杨侗大赦，以王世充为太尉、尚书令，内外诸军事，开太尉府。十二月，被唐军围攻的隋河东守将尧君素制作木鹅，将写有形势的表文系在其颈上，沿河放下，由河阳守军送到洛阳，杨侗见后叹息，拜尧君素金紫光禄大夫。

王世充起初担心人心不服，还讨好杨侗，礼数尚且谦虚恭敬；后来渐渐骄横。一次他入宫接受赐饭，回去后呕吐，怀疑自己的食物被投毒，从此拒绝入朝面圣。皇泰二年（619年）正月，杨侗知道王世充想篡位，却只能让僧人布施宫中丝绸、珍宝给穷人以求神佛庇佑。王世充派党羽张绩、董浚守章善、显福二门，不许宫中杂物出门。

闰正月，夏国主窦建德与王世充结好，遣使奉表于杨侗，受封为夏王。

三月，王世充仗著击破李密的威望，派段达等迫使杨侗加他九锡，杨侗推托王世充击破李密以来没有大功，等天下再平定一些再议，段达说这是王世充想要的，杨侗看了他很久以后只能作罢。段达等人以杨侗诏书名义命王世充为相国，假黄钺，总百揆，进爵郑王，加九锡，备法物，郑国置丞相以下官。段达又以杨侗名义加王世充殊礼。四月初五癸卯日（619年5月23日），王世充派段达和云定兴等十人说服杨侗禅位，杨侗敛膝据案，大怒拒绝，说这是隋高祖的天下和隋世祖的东都，指责对方身为隋朝旧臣却口出此言，神色凛然，侍卫莫不流汗。退朝后，杨侗对著刘太后哭。王世充又派使者说服杨侗，说天下未定需要年长君主，发誓等天下太平、杨侗长大就把皇位还给他，派兄王世恽囚禁杨侗于含凉殿，三次上表辞让及下禅位敕书都不令杨侗得知。两天后，王世充自称皇帝，建立郑朝，改元开明。

退位后

王世充改封杨侗为潞国公，食邑五千户。杨侗每日只能焚香礼佛以祈求平安。五月，尚书左丞宇文儒童、尚食直长宇文温兄弟、尚食直长陈谦、礼部尚书裴仁基、左辅大将军裴行俨父子、散骑常侍崔德本策划攻杀王世充党羽，复立杨侗。事情败露，王世充灭他们三族。

齐王王世恽说这些人谋反是因为杨侗还在，劝王世充杀死杨侗以绝后患。六月，王世充派侄子王仁则和家仆梁百年携鸩酒去杨侗处，对他说：「愿皇帝饮此酒。」杨侗指出这不符合太尉（即王世充）先前的誓言，梁百年想转达王世充，被王世恽拒绝。杨侗自知难逃一死，请求见母亲道别，不获准，于是布下席子焚香向佛像祈祷：「愿生生世世不要再生在帝王尊贵之家」，遂仰药；但一时半刻竟没毒发，最后被缢死，谥号恭皇帝。

评价

• 《北史》论曰：至令赵及燕、越，皆不得死，悲夫！

• 《隋书》史臣曰：至令赵及燕、越皆不得其死，悲夫！

During Emperor Yangs reign

It was not recorded when Yang Dong was born, except that his elder brother Yang Tan (杨倓) 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 (樊子盖) 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 (卫文升), 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 (来护儿) 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 (段达), Yuan Wendu (元文都), Wei Jin (韦津), Huangfu Wuyi (皇甫无逸), and Lu Chu (卢楚). The rebel leaders Li Mi and Zhai Rang soon took advantage of Emperor Yang's departure (along with the elite Xiaoguo Army (骁果)), to capture the food storages Luokou Storage (洛口仓) and Huiluo Storage (回洛仓), 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 (元善达) 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 (庞玉) and Huo Shiju (霍世举) 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 (盖琮), 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 (云定兴) 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 (裴行俨), as well as the officials Yuwen Rutong (宇文儒童), Yuwen Wen (宇文温, 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 (王世恽) 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 (王仁则) 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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