There are hundreds of white supremacist groups in the United States, from Ku Klux Klan organizations to racist skinhead gangs. Most white supremacists don’t actually belong to organized groups, but hate groups provide white supremacists with most of the propaganda, ideology and motivation to act for the whole movement, and are highly visible examples of America’s white supremacy problem.

So how do these hate groups form? The answer to that question isn’t as simple as one might think. In the most basic sense, an extremist group can emerge when one or more individuals devoted to a certain cause recruit other like-minded individuals to form an organized group. In reality, there are usually many complicating factors that affect group formation.

National Socialist Movement members and other white supremacists gather for a swastika burning.

Some extremist movements are more interested in group formation than other, more loosely organized movements. Moreover, the Internet allows extremists to share ideas and strategies easily without people even needing to be involved with a specific group. In some cases, though, the speed and breadth of communication allowed by the Internet can assist group formation.

A new movement is much more likely to form groups by imitating other recently formed groups (see copycatting, below). Group formation in a mature extremist movement is different, because of the presence and effects of all the other, pre-existing groups.

The white supremacist movement is an example of a mature extremist movement with a number of major subsets, from neo-Nazis to white supremacist prison gangs. As a result, group creation within the white supremacist movement can take a number of different forms or, in some cases, combinations of forms.

Here are the eight most common ways white supremacists currently form hate groups in the United States:

1. Graduation

Probably the most frequent way hate groups form is through a process that can be called graduation: when a white supremacist decides to form their own group after having previously spent time as a member of one or more previous hate groups. Having learned about extremism in the original group, the “graduated” extremist then recruits members from the broader white supremacist movement.

Graduation can occur through ambition, when white supremacists seek more status than their current group allows, or through rejection, when they have been expelled from a group. Billy Roper is a good example. A longstanding Arkansas white supremacist who currently heads a small group dubbed the Shield Wall Network, Roper was involved with several white supremacist groups in the 1990s and early 2000s, including the neo-Nazi National Alliance, before disagreements with other National Alliance members caused him to leave that group and form White Revolution. When that group failed, Roper became involved with a Ku Klux Klan group before eventually venturing out again to create the Shield Wall Network.

Groups formed by people with organizational or leadership skills can have considerable staying power compared to other white supremacist groups. Some of the more notorious white supremacist groups in recent American history, such as Aryan Nations and the National Alliance, are good examples of this. However, individuals with true leadership skills are in short supply in today’s white supremacist movement.

One variation on this theme occurs when the “graduate” specifically recruits from members of existing groups of the same type, rather than from the white supremacist movement at large or the general public.

This process, sometimes called cannibalization, is particularly common among Ku Klux Klan groups but can also be found among other types of groups. If a new Klan group’s membership grows, it is often only because it is drawing members away from other, existing Klan groups—and, in turn, the new group’s membership can easily be lured away by an even newer group. This is one reason why most Klan groups in the United States today are only a few years old and why new Klan groups keep forming without increasing the total number of Klan group members.

2. Offshooting

Another common way hate groups form is through off-shooting, which occurs when members of an organization break away to form their own group, often intended to rival or resemble the original entity. White supremacist groups tend to be fractious and susceptible to splintering, which results in new, smaller groups. In the early 2000s, for example, some members of the Hammerskins racist skinhead group broke off to form the Outlaw Hammerskins. More recently, members of the new neo-Nazi group Vanguard America broke away to form the rival groups, Patriot Front and National Socialist Legion.

Members of the (now-defunct) Traditional Youth Movement rally in northern Kentucky.

Sometimes offshoots form as a result of personal conflicts, but in other cases off-shooting may occur because the original group is deemed insufficiently active or radical. In fact, in some cases the original group may not even be white supremacist in nature. For example, several white supremacist groups have been formed over the years by people who had joined other right-wing groups, such as the John Birch Society, only to become disappointed at the lack of explicit racism or anti-Semitism in such groups. They then leave to form their own more radical, more openly racist organizations.

3. Factionalization

Factionalization occurs when an entire group disintegrates into smaller, squabbling factions. In the 2000s, following the deaths of their longstanding leaders, the memberships of two neo-Nazi groups, the National Alliance and Aryan Nations, each split into several different factions that claimed to be the true successor group. Most of the factions lasted only a few years before themselves collapsing.

4. Resurrection

Defunct hate groups don’t always stay defunct. Groups can form when white supremacists attempt to resurrect a defunct but previously well-known group because it has a “brand name” power within the white supremacist movement. The white supremacists attempting the resurrection are often but not always former members of the group.

The single most successful example of resurrection in the history of white supremacy involved the Ku Klux Klan. The original Ku Klux Klan faded away in the 1870s, but decades later, a revival of the group experienced phenomenal success and growth, with the Second Ku Klux Klan expanding to millions of members by the early 1920s. Scandals and bad publicity caused it to decline afterwards. A success on that scale is not likely to happen again.

A more recent Klan example involves the United Klans of America (UKA). Half a century ago, the UKA was one of the largest and most notorious Klan groups in the United States, linked to a number of murders and other acts of violence. It collapsed in the 1980s after being sued by the Southern Poverty Law Center. After a failed attempt in the 1990s to resurrect the group, a longstanding Alabama Klan figure, Bradley Jenkins, tried again in 2015.

After its aforementioned split, Aryan Nations also experienced attempts at resurrection, including an effort to recast it as a biker group dubbed Aryan Nations Sadistic Souls. The Sadistic Souls claim to be the true successor to Aryan Nations because one of its members says he is the nephew of the original group’s founder.

5. Subcultural Groups

American society contains many subcultures—people with shared dress, rituals, language, music and more. Occasionally a subculture will be exposed to white supremacist ideology and parts of it may start to incorporate that ideology into its own subcultural activities—including the formation of groups within that subculture. The most famous example of this sort of evolution occurred in Great Britain in the 1970s, when the skinhead subculture developed a racist variant. By the 1980s, that strain had found its way to the United States, where many racist skinhead groups subsequently formed.

Similarly, some white supremacist gangs emerged from the 1980s California punk scene. Some, such as Public Enemy Number One (PEN1), still exist today, though the present-day gang—essentially a white supremacist prison gang—bears little resemblance to its original iteration.

Today, the alt right segment of the white supremacist movement is a similar example of subcultural emergence. The alt right evolved from a variety of beliefs and subcultures, most significantly the online gaming subculture, the misogynistic subculture of the “manosphere,” and the imageboard subculture of sites like 4chan and 8chan.

To date, the alt right has not tended strongly towards group formation—probably a relic of its on-line origins—but groups that have emerged carry the DNA of their foundational subcultures.

Just as hate groups can evolve from subcultures, they can also emerge from white supremacist social scenes. White supremacists often arrange formal or informal social gatherings of like-minded people in a particular geographic area, such as a “meet up” of white supremacists that might revolve around a barbecue. Some may socialize on a regular basis with other white supremacists in an area, like some of the Daily Stormer-associated “book clubs” that have recently appeared around the country. These social situations can occasionally prompt friends or acquaintances to decide to go to the “next level” and actually form a more formal group. In rare circumstances, members of a particular white supremacist family may form the nucleus of such a group rather than evolving from a social circle.

6. Copycats

Copycatting occurs when people seek to replicate a particular type of extremist group in their own location. This is not simply a case of an existing extremist group expanding into new geographic areas, though the distinctions may blur if the extremist group is highly decentralized.

Copycatting is most common within new extremist movements and is a significant way such movements spread. Because the white supremacist movement is an old and established movement, it offers fewer opportunities for large-scale copycatting than some other extremist movements have, but the process can occasionally occur, particularly when a new variation of white supremacy or a new type of group emerges.

Perhaps the best example of this phenomenon occurred in the 1980s with the nationwide proliferation of white supremacist prison gangs. For many years, the Aryan Brotherhood (based in the California and federal prison systems) was the only major white supremacist prison gang, but as various prison systems desegregated in the 80s, inmates copied the idea of the Aryan Brotherhood in their own state prison systems, often even stealing the name: Aryan Brotherhood of Texas, Ohio Aryan Brotherhood, Arizona Aryan Brotherhood, and so forth. These gangs were not chapters or subgroups of the original Aryan Brotherhood but rather independent and unrelated copies of it.

Copycatting can also occur on a smaller scale within the white supremacist movement, such as the so-called “white student unions” that some young white supremacists have attempted to establish at universities. Most of these groups, however, were very short-lived.

7. Social Media Groups

In recent years, a number of new extremist groups have emerged from social media. For example, extremists may create a Facebook “group” that eventually takes on a life of its own and evolves into an actual “in real life” group. Thanks to the speed and reach of social media, groups organizing by this method can spread quite quickly.

In early 2016, for example, the Soldiers of Odin USA formed using Facebook, bringing together white supremacists, anti-government extremists and anti-immigration extremists to oppose immigration and refugees. Within just a couple of months, thousands of people had expressed support for or affiliation with the Soldiers of Odin and chapters had formed in most states. However, like many groups that form on social media, members were spread widely but thinly and the number of people actually committed to the group turned out to be considerably fewer than suggested by its Facebook statistics.

8. Mutations

Some extremist groups don’t form as extremist groups—they form as some other sort of organization but mutate over time into something more extreme. The most famous example of this type of group formation is the original Ku Klux Klan, which was formed as a social club in the mid-1860s by a small group of friends and Confederate veterans in Tennessee. It quickly evolved into something far more sinister, and within short order it became a violent terrorist movement that threatened Reconstruction state governments in the South.

In some cases, a mutation is contingent on a dominant or charismatic personality. In the 2000s, the Michigan State University chapter of the conservative college group Young Americans for Freedom became so radicalized under the leadership of Kyle Bristow that the chapter essentially became a hate group. Bristow eventually resigned from the group, going his own way as a white supremacist, and in 2016 founded his own hate group, the so-called “Foundation for the Marketplace of Ideas.”