A clan is an unorganized team of people under a specific uniform or color. Clans were the main source of "army" related conflict from 2005 to 2007, where most clans were phased out. Some clans have seen organization, such as the early Romans, which despite being organized like an army, is widely accepted to be a clan. Rogue armies can also be considered clans.
Clans have always been seen in Club Penguin history, even carrying onto the CPPS era of Club Penguin. Most type of clans and some major clans will be listed here.
A proto-clan is a heavily unorganized clan that predates World War I, the first major war consisting of clans. These proto-clans were very uncommon compared to clans today. Most proto-clans were clans based on role-play characters created by Club Penguin itself. Some proto-clans are the Penguin Secret Agency, which was formed circa October 24th, 2005 to May 17th, 2010 (way after the dawn of proto-clans) and chefs (c. February 24th, 2006). More formally made proto-clans are the Club Penguin Army (the first army in CPA history) and the proto-Romans (founded in c. February 3rd, 2006). Arguably, color clans could also be considered proto-clans.
The color clans likely first sprung up in 2005 and early 2006, making these color clans proto-clans. However, the true color clans began to show up after August 11th, 2006, after the Sports Party came to light. Many players would pick a color and it's respective color related sports gear to show their allegiance. These are the first clans to be considered "real" in CPA history. These clans saw action in World War I, which lasted from August 11th, 2006 to early 2007, traditionally. Most notably the Reds grew to prominence after Korn, partially organized the clan into a large force, wiping out the rest of the clans in late 2006/early 2007. The Reds soon died. The other biggest color clan was the Blues.
The traditional clans were the series of clans founded in summer 2006 up until 2007. These clans helped kick start World War II, which eventually killed off most of the traditional clans. Many of these clans sparked special uniforms and low organization. Some clans organized themselves on the Miniclip forums for Club Penguin, which caused some of these clans to be labeled as "organized clans" or simply an "army". These clans consisted of the Penguin Secret Agency, the Pirates (not to be confused with the later formal Pirates), the Vikings, the Club Penguin Army, the proto-Nachos, and tens of others. Some organized clans/armies included the Romans, which was organized in late September/early October by Explorer7777, the Army of Club Penguin (the first formal army of modern CPA history), and the Club Penguin United Nations Space Commission.
Later clans & rogue armies
The later clans, sometimes referred to as gangs, are clans formed after the era of the clans collapsed in 2007. Many unorganized groups still continued to flourish within the community, at minor levels. A good example is the Elite Penguin Force, which replaced the PSA in the Club Penguin game in 2010. More recently, clans such as the Gangrene Gang and the Pizza Bois United have formed. A new era of clan-like organized armies also emerged overtime. These are known as rogue armies, which take advantage of role-play costumes and popular costumes to either build an army to take in recruits. Some examples of these in more recent times are the Onlooking Snow Ninjas, formed in 2015. Groups such as the Tubas, the Pizza Bois, the Pizza Bros, and the Pizza Federation have since formed as rogue armies/gangs/clans in recent times since 2017. Rogue armies have a trend of lacking success in the army community, however. The Pizza Federation has obtained moderate success despite being a rogue army. They have been known for their attempts to shift away from that status. Armies like the United Republic of Penguins have taken advantage of parties in its later eras, such as the Christmas Party on Club Penguin Rewritten, to pull recruits utilizing rogue army tactics.