How do we understand the purge of Jang Song Thaek? The Korean official and uncle of the leader, Kim Jong Un, was dragged out of a meeting of the Korean Worker’s Party Central Committee by uniformed officers, removed from all offices, and executed days later. He was accused of "anti-party, counterrevolutionary factional acts" and "attempting to undermine the unitary leadership of the party," along with a litany of other charges, including corruption, womanizing, and selling the country’s resources cheaply. The state news agency called him "despicable human scum" and "worse than a dog."

It is hard to speculate about such an opaque society. We simply do not know enough about power dynamics inside the Kim Jong Un regime to determine how much of a threat, if any, Jang posed to the young leader. But it’s hard to ignore the fact that, as ruthless as North Korean leaders may be, bouts of Shakespearean violence like this are highly unusual. The last execution of such a high-ranking official was just after the Korean War.

There had been indicators that something was shifting. In August 2013, changes were made to the ten points of the Monolithic Ideological System, a system first developed in 1967 by the young leader’s grandfather to ensure absolute loyalty to the unitary leader, and to him alone. This was as important a step in regime consolidation today as it was in 1967. The meaning would have been unmistakable to the North Korean people and to aspiring cadres: “There are not two suns in the sky, nor two sovereigns over the people.”

Jang, who had been purged at least twice before, still cast a long shadow over the young leader and was perceived by many as a type of regent. Kim Jong Un’s actions send a clear signal that there is no No. 2 in absolutist North Korea.

This is not the first time top North Korean officials have been purged and denounced for alleged anti-party and anti-people factional activities. Some of the more well-known purges of alleged high-level “factionalists” occurred in 1953, 1956, and finally, in 1967. Yet, executions, at least of top officials, are a rare event.

The 1953 purge occurred toward the end of the Korean War. Though no evidence has emerged to support the claim, a number of prominent officials, primarily with southern Korean origins, were accused of being agents of the United States and of planning a direct challenge to North Korean founding ruler Kim Il Sung’s authority. Most of the alleged conspirators, including the most well-known Korean communist of the colonial era, Pak Heonyeong, were executed. This was the first, and according to existing evidence, last purge that resulted in the execution of such a high-ranking official.

The next major purge of highly-placed officials came in 1956 on the heels of a two-and-a-half year debate over economic development. The North Korean leadership was divided into two camps. Kim Il Sung’s camp supported a policy of general industrialization, with a focus on heavy industry. On the other side of the debate was a broad coalition of ethnic Koreans who had returned to northern Korea from the Soviet Union and China after the country’s 1945 liberation from Japan. They advocated for the replication of the post-Stalin Soviet development strategy that prioritized consumer goods and improved living standards. From early 1956 Kim’s opponents also began to criticize the North Korean leader’s Stalin-inspired cult of personality after the new Soviet leader, Nikita Khrushchev, delivered a scathing attack on his predecessor that February. Recognizing that the Soviet-Koreans and China-returned Koreans would continue to serve as conduits of outside (i.e. Soviet and Chinese) influence as long as they remained in positions of authority, Kim Il Sung purged his opponents, sending them to manage pig farms and rural cement factories. This process lasted nearly two years and affected all levels of society. The purge was designed primarily to limit the influence of Moscow and Beijing on the future trajectory of North Korean political and economic developments.

The 1967 purge of the so-called Gapsan faction was the most significant in terms of repercussions. At a time when North Korea was faced with tremendous security challenges, particularly from the radical Cultural Revolution, several senior officials began to challenge economic policies and the expansion of Kim Il Sung’s cult of personality. The criticism was similar to that made by the Soviet-Koreans and China-returned Koreans from 1953 to 1956, except the critics had been close allies of Kim Il Sung, including Pak Geumcheol, the fourth ranking member of the KWP CC’s Political Committee who foreign diplomats described as Kim’s “right hand man.”

Starting in late 1966, Pak and his associates began to criticize the continued mobilization of the nation through the so-called Byungjin line (reintroduced in March 2013 by Kim Jong Un) that focused on the simultaneous development of heavy industry and national defense. Pak and others gave voice to the frustrations of the North Korean people by suggesting that it was finally time to focus on elevating living standards in the DPRK.

Connected to Pak Geumcheol’s efforts to position himself as the champion of the North Korean masses was his criticism of the expanding cult of personality surrounding Kim Il Sung. Indeed, this may have been the real source of Pak’s grievances. Everyone but Kim Il Sung was being written out of the history of the anti-colonial struggle. This must have greatly frustrated Pak, who had spent many years in prison after being captured by the Japanese for his direct support of Kim Il Sung’s anti-Japanese guerrilla activities.

In March 1967, Kim Il Sung delivered a speech in which he warned Pak and his colleagues against engaging in activities of “individual heroism.” Kim placed great emphasis in his speech on accepting the orders of the Party and the leader unconditionally, and on establishing a Monolithic Ideological System. The experiences of earlier debates likely reinforced Kim Il Sung’s desire to eliminate debate so that he could carry out the policies he considered necessary for the greater good of the country. The Monolithic Ideological System, therefore, would suppress pluralism within the party.

Pak and his associates were purged in May of 1967 and exiled, not executed. After being charged with a litany of crimes, many were sent to manage rural factories.

In 1974, the ten points of the Monolithic Ideological System were updated when Kim Jong Il was anointed, at least internally, as Kim Il Sung’s successor. Once Kim Jong Il was designated successor, he co-ruled with his father, Kim Il Sung, as one unit. The updated ten points advanced the cult of Kim Il Sung (and further extended it to co-ruler Kim Jong Il). The ten points also established more control over every aspect of life as each point was subdivided, glorifying and demanding absolute loyalty to Kim Il Sung and Kim Jong Il. Every member of society was expected to memorize and live by these rules.

Although they did not suffer the same fate as Jang Song Thaek, the uncle of Kim Jong Un by marriage, Jang was not even the first member of the family to be purged under the unitary leadership system. Indeed, shortly after the establishment of the Monolithic Ideological System in 1967, Kim Jong Il competed with his uncle Kim Youngjoo, the heir apparent at the time, for the position of successor. By the early 1970s, Kim Jong Il’s rising star had eclipsed that of his uncle, who was purged in 1976 and exiled to one of the country’s northernmost provinces where he was placed under house arrest in 1976, just over a year after the Ten Points of the Monolithic Ideological System were updated. Kim Youngjoo was permitted to return to Pyongyang only in 1993, and was given the ceremonial title of honorary Vice President of the Presidium of the Supreme People’s Assembly, the rubber stamp legislative body of the DPRK.

Fearing competition, Kim Jong Il also exiled his half-brothers Kim Pyong-Il and Kim Yong-Il, sons of Kim Il Sung’s second wife, Kim Song-ae. Kim Pyong-Il was exiled to Poland, where he has served as the DPRK’s ambassador since 1988. Kim Yong-Il died in exile in Germany in 2000.

The timing of the recent update to the ten points of the Monolithic Ideological System suggests that the purge and execution of Jang Song Thaek should be analyzed primarily in the context of efforts to solidify the unitary leadership of Kim Jong Un. We simply do not know if Jang posed a genuine threat to Kim Jong Un’s authority.

But what is clear is that Jang’s execution is a shocking development, reversing a trend to simply exile alleged “factionalists.” Maybe Kim Jong Un does not yet feel as secure as his forebear did in 1956 and 1967 when he considered it sufficient to exile his opponents. Or maybe, like his grandfather who ordered the execution of Pak Heonyeong just after the Korean War, he believed that Jang Song Taek was too much of a threat, even in captivity.