Background
As a modern political historian, Laridahuizhansunchen must be understood within the vicious cycle of "regent replaces emperor" that characterized late Sunwu. In the mere six years following Sun Quan's death, Wu underwent the successive shocks of: Zhuge Ke's regency; Zhuge Ke killed by Sun Jun; Sun Jun governing and then dying; Sun Jun's cousin Sun Chen taking power; Sun Chen deposing the young emperor Sun Liang and installing Sun Xiu. Each regent transition was accompanied by a large-scale purge: Zhuge Ke's entire clan was executed, Sun Jun killed Teng Yin and Lv Ju, Sun Chen then killed Wang Dun and deposed Sun Liang [c:17511]. Imperial power and the authority to command the palace guard had completely separated; the emperor was little more than a puppet on the regent's strings. When Sun Xiu ascended the throne (258) the situation he faced was this: he himself had been installed as a figurehead by Sun Chen from the position of Prince of Langxie, and the entire court understood the reality. This was the political starting point of the Laridahuizhansunchen event.
Principal Figures
Sun Xiu was Sun Quan's sixth son, composed and studious, already twenty-four years old when he came to the throne — more mature than Sun Liang, and capable of "feigning weakness while biding time." Sun Chen was Sun Jun's cousin, became Grand General, Chancellor, and Marquis of Yongling all at twenty-eight, personally commanded the central palace garrison troops, arrogant and imperious in character, and had repeatedly killed prominent ministers. In the balance of power, measured purely in military terms, the two were in absolutely unequal positions. Around Sun Xiu was Left General Zhang Bu — a close retainer from his days as Prince of Langxie, genuinely trustworthy — and the elder general Ding Feng, the last surviving veteran of Wu's military of founding-generation status, a soldier who had come through Chibi and Yiling; no one dared move lightly against his prestige. There were also two lower-level informants, Wei Miao and Shi Shuo, who served as key nodes for intelligence transmission before the coup [c:17510]. Around Sun Chen were four cousins controlling the palace garrison troops — the force Sun Xiu most feared.
Core Issues
The central issue of the operation to kill Sun Chen was "how to recover imperial power without triggering a military rebellion." Directly ordering troops against Sun Chen was almost impossible — the palace garrison authority lay with the Sun clan; openly issuing an edict to remove him was equally impossible — Sun Chen could simply depose the emperor in return. The only remaining path was "exploit a ritual occasion combined with minimal force and the creation of surprise to carry out a precise decapitation." Sun Chen was actually on guard: after being turned away from the New Year's toast, he had already warned in Zhang Bu's presence that "I'll let you see sooner or later," and he had also redistributed fifteen thousand elite troops from the central camp to garrison Wuchang, emptying the weapons stockpile [c:17510]. This was the classic "move armed forces out of the capital before a coup" — but simultaneously a self-undermining act. Once the main force had been transferred out of Jianye, the palace garrison nominally still answered to the Sun clan but was in practice thinly controlled, creating a window for Sun Xiu to strike.
Ding Feng's plan was simplicity itself — "when he comes to court on the Lari festival day, we simply arrange a grand assembly of officials; seize him at the banquet." Two points made this plan viable: first, the Lari grand assembly was a formal state ritual, and Sun Chen as Chancellor was required to attend — and by ritual protocol could not come armored or with troops; second, the operation at the scene required only thirty-odd armed attendants, with Sun Xiu himself presiding from the imperial seat while Zhang Bu entered with sword in hand and proclaimed "by imperial edict, seize the traitor Sun Chen" — the lowest-cost possible coup [c:17511]. This design of "binding him with ritual, justifying it with an edict" is a high-order example of political theater.
Political Consequences
At the moment of Sun Chen's execution, Sun Xiu upbraided him: "Why did you not exile Teng Yin, Lv Ju, and Wang Dun?" — reciting the names of all those Sun Chen had killed, amounting to a public declaration before the assembled officials: "This settlement is not a case of ruler and subject striking at each other, but rather rectifying injustices done to those who were wrongfully killed." This single utterance raised the action's legitimacy from "internecine strife" to "the rendering of justice." The consequences spread immediately: first, Sun Chen's four cousins — Sun En, Sun Ju, Sun Gan, and Sun Kai — were at once executed, and palace garrison authority reverted to the imperial household; second, Sun Xiu posthumously honored the deposed Sun Liang as Prince of Kuaiji and restored the reputations of Zhuge Ke, Teng Yin, Lv Ju, and others who had been wrongfully killed, sending a clear political signal of sweeping repudiation of the entire era of regent domination; third, Sun Xiu in the short term established an advisory administration centered on Zhang Bu and Ding Feng with Puyang Xing and others as governing assistants, and Wu politics entered a few years of relative stability. But this stability was fragile — Sun Xiu himself died five years later (264), and Wu fell into the tyranny of Sun Hao's era.
Counterfactual Analysis
The first counterfactual: had Sun Chen not transferred his main force out of Jianye. Even if the Lari assembly trap had been set, his brothers holding the city with their private troops would have meant the coup could have ended in reverse — Sun Xiu seized, and Wu plunging into an even deeper layer of regent domination. This counterfactual reveals that "the regent transferring his troops out of the capital" is a universal political trap: it signals confidence in the capital's security, but simultaneously weakens one's ability to respond to a surprise attack. The second counterfactual: had Sun Xiu shown his anti-Sun Chen intentions early after ascending the throne. Given the decisiveness with which Sun Chen had killed Zhuge Ke and deposed Sun Liang, he would not have waited for Sun Xiu to "grow" to the point of being able to challenge him. Sun Xiu's success was entirely because he had, during the preceding months, performed the image of a "compliant and docile" ruler, lulling Sun Chen's guard and redirecting his attention toward mobilizing external forces. This "feigning weakness while waiting for the moment" is the oldest and most effective counter-regent pattern in Chinese politics. The third counterfactual: had Ding Feng not been alive. This elder general provided not only the tactical plan but, more importantly, his prestige — his presence lent the action the political endorsement that "executing Sun Chen is a legitimate military order, not a private brawl." Without Ding Feng, Sun Xiu would have been almost unable to find a veteran who could command the moment. The core of this success was not Sun Xiu's superior strength, but his ability to identify his scarcest resource — historical seniority — and place it in the most critical position. This is the most valuable form of self-knowledge in political strategy.