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High Growth and Organization — In the Shadow of a Swelling Economy

In the 1960s, behind the rapid growth of the Japanese economy, the violent gangs were transforming from local groups into nationwide organizations. Wide-area expansion and the building of hierarchies, recurring conflicts, and the police 'summit operations.' Within the bounds of the public record, we trace calmly the contours of an underworld that swelled in the shadow of growth.

June 13, 2026

Up to now, we have watched how, in the chaos and the black markets after defeat, an illicit order spread into the gaps left where the function of the police had weakened. In time Japan completed its recovery and went on to grow its economy at a speed that astonished the world. This was the period of high economic growth, said to have continued from around 1955 to 1973. Yet behind those bright figures, the violent gangs—until then scattered and separate from region to region—were transforming into large organizations spread across the whole country. In this installment, we look at the process by which the underworld became organized in step with the swelling of the economy, keeping within the range of publicly confirmed and reported facts, and without rushing to judgment. One thing to keep in mind: this is not a tale told to display ‘the power of force,’ but an inquiry into why such expansion could happen at all, and into the conditions that allowed it.

  1. 1960

    A large-scale rivalry and conflict broke out in Osaka and was widely covered in the press. It is said to have been one of the events that drew public attention to power struggles spanning multiple areas.

  2. 1961

    It is recorded that the government decided, at a cabinet meeting, on measures concerning the prevention of violent crime. Administrative concern over public order was rising.

  3. 1964

    The Metropolitan Police Department established a headquarters to crack down on organized violence, and a nationwide simultaneous crackdown (later called the summit operation) is said to have begun. The same year, the Olympics were held in Tokyo.

  4. 1969

    It was reported that the series of crackdowns known as the First Summit Operation had reached, roughly speaking, a turning point.

From Local Groups to a Nationwide Organization — The Change Called Wide-Area Expansion

When the violent gangs of the 1960s are discussed, a word often raised is ‘wide-area expansion.’ Until then, the groups that traced their lineage from the gambler and street-vendor traditions were largely bound to particular plots of land or entertainment districts—local groups, so to speak. In this period, however, it is recorded that several organizations extended their reach across prefectural borders and brought groups in various places under their umbrella.

The name most often cited as representative of this is the Yamaguchi-gumi, based in Kobe. According to press and encyclopedia accounts, under the leadership of Kazuo Taoka (1913–1981), said to be its third-generation head, the organization advanced into various parts of the country from the late 1950s into the 1960s, expanding rapidly while repeating cycles of conflict and growth. What had been a group of a few dozen people at the time of his succession is said to have grown by around 1980 into an organization that held numerous affiliated bodies spanning several prefectures and a force of more than ten thousand. That said, this is the example of a single organization, and it should not be overlooked that during the same period various groups across the country were repeatedly joining and splitting apart.

Why did such wide-area expansion become possible? The background, it is thought, lay in high growth itself. The population moved into the cities, entertainment districts bustled, and great sums of money and numbers of people moved through sites such as construction, the ports, and show business—wherever that current ran, the illicit groups found new footholds. The expansion of the economy became, ironically, the very soil that supported the expansion of the underworld: that is one way of viewing this era.

Hierarchy-Building and Ceaseless Conflict

Advancing alongside wide-area expansion was ‘the building of hierarchies’—that is, the movement by which large organizations took local groups under their umbrella and bound them together through vertical ties. The old fictive bonds of boss and follower were recast into the layered structure of large organizations that straddled prefectures. Through this, it has been noted, the upper organizations found it easier to gather money over a wide range in the form of tribute paid up from those beneath them.

The expansion of power, however, repeatedly gave rise to fierce confrontation. The large-scale conflict said to have occurred in Osaka in 1960 remains on record as one such example. According to press and encyclopedia accounts, this confrontation is said to have greatly shifted the map of regional power. Such conflicts did not remain disputes between the parties involved; firearms were used, and they frequently brought about situations that threw the surrounding citizens into fear. The dread of violence being carried into entertainment districts and onto the streets became, from this period, something concrete within society.

What must be emphasized here is not to depict the conflicts as ‘striking incidents.’ There were people who were really hurt and who lost their lives, and there were residents who lived in fear of being caught up in it. The expansion of the underworld bore down heavily upon ordinary people as a burden that threatened the safety of their communities.

The State Begins to Move — The Turning Point of the Summit Operation

Against the ever-swelling violent gangs, the administration and the police did not merely stand by. According to the record, in 1961 the government is said to have decided at a cabinet meeting on measures concerning the prevention of violent crime. And in 1964, with concern over public order rising ahead of the Olympics held in Tokyo, the Metropolitan Police Department established a headquarters to crack down on organized violence and set out on a nationwide simultaneous crackdown. This would later come to be called the ‘summit operation.’

This operation, it is explained, aimed not at the lower ranks but at the core of the organizations, seeking to drive them toward the arrest of their leaders and the dissolution of their bodies. Wide-area organizations including the Yamaguchi-gumi became targets; many leaders were arrested, and a number of affiliated bodies were reported to have dissolved. The press reported that the hand of investigation reached the businesses said to be sources of funds, and that there were cases in which organizations withdrew from those fields. The series of crackdowns is said to have reached one turning point around 1969.

The summit operation is positioned as one of the earliest efforts in which the state confronted in earnest the expansion of the violent gangs. As later history shows, however, this did not make the underworld disappear. The organizations changed their form and survived by clinging close to the boundary between the legal and the illegal. The tug-of-war between crackdown and survival would continue for a long time thereafter.

And so the 1960s are remembered as an era in which the violent gangs transformed from local groups into nationwide organizations, and at the same time the state began to grope for a framework to crack down on them. The growth of the economy, the expansion of the underworld, and the crackdown against it—the tug-of-war among these three became the basic composition running through the decades that followed. Next time, we turn our eyes to the very flow of money: by just what mechanisms did these swollen organizations obtain it.

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