Aside from the details of growing your economy and expanding your population, you also have to contend with other European colonists and with natives. The cultures that the European invasion of the Americas forced into contact couldn’t have been more different.

Generally speaking, the Amerindians had a long-standing, deeply-rooted respect for nature and viewed themselves as an integral part of the ecosystem. Some of the concepts that Europeans found basic to society such as “ownership” and “progress” meant little or were interpreted in totally different ways by these American natives. The vast differences which separated Amerindians from Europeans created misunderstandings that would flash into violent confrontations. Looking back, the friction seems inevitable— everything the European needed to grow and prosper (in his way of thinking), the aboriginal needed to maintain. Europeans were consumers, the natives, conservers.

TRIBES

None of the aboriginal tribes are human player controlable. They are all controlled by the game's Artifical Intelligence (AI). They are three different categories of native tribes: nomadic (Apache, Sioux, Tupi), woods-dwellers (Arawak, Cherokee, Iroquois) and city-dwellers (Aztec and Inca). They are represented by teepees, long-houses and pyramids or terraced stone buildings respectively.

Each tribe consists of several settlements scattered over an area of the map. A settlement is the dwelling place of several braves that patrol the map nearby. Cities are much better defended than the other native settlements because of the large populations that dwell there. In addition, cities are wealthier than other settlement types -- according to European standards -- and are therefore much more likely to yield large treasures if captured. Villages are not as populated as cities, but are still quite well defended. Camps are poorly defended.

In general, the natives remain a mysterious entity, moving silently through the woods and plains of their land. The attitude of each tribe toward the settlers is a source of worry and concern to all, but is cloaked in mystery. The native settlements each have an identity of their own, but a general tribal uprising — involving all settlements of that tribe — can occur if your actions toward some villages of the tribe are insensitive or brutal. In addition to overall tribal attitude, each person settlement of a tribe has its own feeling toward you. person settlement attitude is called alarm and contributes to overall tribal anger.

APACHE
They are representative of the great nations of the American Southwest. They were nomads with advanced agricultural techniques. Fierce warriors, they were among the last tribes to be subdued by the invaders. Their entire culture was transformed by the fight for survival with Europeans. They became desert wanderers in an attempt to remain untouchable by European military tactics, which centered upon destruction of military bases. From their entry on Wikipedia:

Apache is the collective name given to several culturally related tribes of Native Americans, aboriginal inhabitants of North America, who speak a Southern Athabaskan language. The modern term excludes the related Navajo people. The Apache peoples migrated from the Northern Plains into the Southwest relatively recently. Noted leaders have included Cochise, Mangas Coloradas, and Geronimo. The U.S. Army found them to be fierce warriors and skillful strategists. [..] [Spanish conquistador Francisco Vásquez de Coronado wrote:]

"After seventeen days of travel, I came upon a rancheria of the Indians who follow these cattle (bison). These natives are called Querechos. They do not cultivate the land, but eat raw meat and drink the blood of the cattle they kill. They dress in the skins of the cattle, with which all the people in this land clothe themselves, and they have very well-constructed tents, made with tanned and greased cowhides, in which they live and which they take along as they follow the cattle. They have dogs which they load to carry their tents, poles, and belongings."

ARAWAK
They represent the island-dwelling cultures of the Caribbean -- those first encountered by Columbus. These were friendly natives who at first welcomed the invaders with open arms and generosity. After extremely cruel treatment at the hands of the Spaniards, however, they became quite vicious. From their entry on Wikipedia:

The term Arawak... was used to designate the friendly Amerindians encountered by the Spanish in the Caribbean. [..] The group belongs to the Arawakan language family and they were the natives Christopher Columbus found when he first landed in the Americas. The Spanish described them as a peaceful, gentle people[... Columbus wrote the following in his log:]

"They willingly traded everything they owned... they do not bear arms, and do not know them, for I showed them a sword, they took it by the edge and cut themselves out of ignorance... Their spears are made of cane... they would make fine servants... With fifty men we could subjugate them all and make them do whatever we want."

AZTEC
They represent all the advanced civilizations of Mesoamerica. They built magnificent stone cities on floating islands in tremendous lakes. Large pyramids served as backdrops for religious ceremonies. They and their subjects were heavily involved in warfare with a long heritage of art and culture. From their entry on Wikipedia:

The Aztecs were a Mesoamerican people of central Mexico in the 14th, 15th and 16th century. They were a civilization with a rich mythology and cultural heritage. Their capital was Tenochtitlan on the shore of Lake Texcoco – the site of modern-day Mexico City. [..] The Aztec Empire is not completely analogous to the empires of European history. Like most European empires, it was ethnically very diverse, but unlike most European empires, it was more a system of tribute than a single system of government. [..]

The Aztecs were conquered by Spain in 1521, when after long battle and a long siege where much of the population died from hunger and smallpox, Cuauhtémoc surrendered to Hernán Cortés (a.k.a. "Cortez"). Cortés, with his up to 500 Spaniards, did not fight alone but with as many as 150,000 or 200,000 allies from Tlaxcala, and eventually from Texcoco, who were resisting Aztec rule. He defeated Tenochtitlan's forces on August 13, 1521.

CHEROKEE
They represent the Woodlands Indians of the southeastern areas of North America. These were some of the most highly developed civilizations existing in America at the time of European colonization. Unlike the Aztec and Inca peoples they were not builders of vast stone structures and cities, but rather tenders of forests. They worked to balance their needs with the needs of the animals and plants of their environment in order to achieve harmony. From their entry on Wikipedia:

The Cherokee... are a people native to North America who at time of European contact in the 16th century inhabited what is now the eastern and southeastern United States before most were forcefully moved to the Ozark Plateau. They were one of the tribes referred to by Native Americans as the Five Civilized Tribes. [..] Beginning at about the time of the American Revolutionary War (late 1700s), divisions over continued accommodation of encroachments by white settlers, despite repeated violations of previous treaties, caused some Cherokee to begin to leave the Cherokee Nation. [..]

Cherokees were displaced from their ancestral lands in North Georgia and the Carolinas because of rapidly expanding white population, as well as a Gold Rush around Dahlonega, Georgia in the 1830's. [..] The Dawes Act of 1887 broke up the tribal land base. Under the Curtis Act of 1898, Cherokee courts and governmental systems were abolished by the US Federal Government. [..] However, the Cherokee Nation recognized it needed leadership and a general convention was convened in 1938 to elect a Chief. They choose J. B. Milam as principal chief, and as a goodwill gesture Franklin Delano Roosevelt confirmed the election in 1941.

INCA
They represent the advanced civilizations of western South America. The peoples of the Andes and coastal plains were highly skilled builders and farmers. Their cities were made without mortar of any kind; instead, huge stones were carved and fitted carefully together to form structures that still stand today. Evidence of advanced farming techniques and scientific experimentation indicates that they were one of the most agriculturally advanced civilizations that ever existed. From their entry on Wikipedia:

The Inca Empire... was an empire located in South America from 1438 AD to 1533 AD. Over that period, the Inca used conquest and peaceful assimilation to incorporate in their empire a large portion of western South America, centred on the Andean mountain ranges. The Inca empire proved short-lived: by 1533 AD, Atahualpa, the last Sapa Inca, was killed on the orders of the Conquistador Francisco Pizarro, marking the beginning of Spanish rule. [..]

The new Spanish rulers brutally repressed the people and their traditions. Many aspects of Inca culture were systematically destroyed, including their sophisticated farming system. The Spanish used the Inca mita (mandatory public service) system to literally work the people to death. One member of each family was forced to work in the gold and silver mines... When one family member died, which would usually happen within a year or two, the family would be required to send a replacement. [..]

The English term Inca Empire is derived from the word Inca, which was the title of the emperor. Today the word Inca still refers to the emperor, but can also refer to the people or the civilization, and is used as an adjective when referring to the beliefs of the people or the artifacts they left behind.

IROQUOIS
Traditionally, they and the Cherokee are similar. They had similar dwellings, religious beliefs, and cultural icons. These peoples, however, developed an elaborate democratic government that in many ways formed the basis for the Constitution of the United States of America. They were a coalition of as many as six different tribes with elected representatives and mutual protection agreements. From their entry on Wikipedia:

The Iroquois Confederacy... is a group of First Nations/Native Americans. The Confederacy was originally based in, at the time of the arrival of the Europeans, in what is now upstate New York. Now they also occupy territory in Ontario and Quebec. This union of nations was established prior to major European contact, replete with a constitution recorded with special beads called wampum that served the same purpose as money in other cultures. Most Western anthropologists speculate that this Constitution was created between the middle 1400s and early 1600s, but other scholars who account for Iroquois oral tradition argue that the event took place as early as 1100... The United States Constitution was partly modelled on the Iroquois League Constitution.

The two prophets, Hiawatha and "The Great Peacemaker", brought a message of peace to squabbling tribes. The tribes who joined the League were the Seneca, Onondaga, Oneida, Cayuga and Mohawks. Once they ceased (most) infighting, they rapidly became one of the strongest forces in 17th and 18th century northeastern North America. [..] According to [historian] Francis Parkman, the Iroquois were at the height of their power in the 17th century with a population of around 12,000 people.

SIOUX
They represent the aboriginals of the Great Plains in the northwestern areas of North America. They were nomads that followed buffalo herds. Often called the world’s best light cavalry, their warriors were highly talented horsemen. They obtained the horse from the Spanish in the early 1500s, and by the time of their first encounters with other Europeans were formidable mounted warriors. They relied upon the horse to such an extent that their culture is often called a “horse culture.” From their entry on Wikipedia:

[Also known as t]he Lakota, [they] are part of a band of seven tribes that speak three different dialects, the other two being the Dakota and the Nakota. The Lakota are the western most of the three groups, occupying lands in both North and South Dakota. The Nakota, the smallest division, reside on the Yankton reservation in South Dakota, the Northern portion of Standing Rock Reservation, and Canada (the Stoney and Assiniboine), while the Dakota live mostly in Minnesota and Nebraska. [..]

The name Sioux was created by the French Canadians... This term is popularly interpreted as an insult but it could refer to a time when the Dakota people, like the Creek, were known to revere serpents... Today many of the tribes continue to officially call themselves 'Sioux' which the Federal Government of the United States applied to all Dakota/Lakota/Nakoda people in the 19th and 20th centuries.

TUPI
They represent various jungle-dwelling coastal communities of the Amazon Basin and eastern South America. Primarily stone-age peoples, they were able to manage a quite productive lifestyle from their jungle habitat. They participated in ritual cannibalism as a source of protein, which was rare in their jungle environment. The Europeans viewed this as evidence of base savagery. Here is their complete entry on Wikipedia:

Tupi is the name of one of the main ethnic groups of Brazilian indigenous people, together with the related Guarani. They first inhabited the Amazon rainforest, then spread southward and gradually occupied the Atlantic coast. From the sixteenth century onward the Tupis, like other natives from the region, were assimilated, enslaved or simply exterminated by Portuguese and Spanish settlers, nearly leading to their complete annihilation as a culture. The remnants of these tribes are today confined to indigenous reservations or acculturated to some degree into the dominant society.

In southeastern Brazil they are an important presence in the genetic pool, while constituting a considerable portion of the lower classes in the North, Northeast, and Center-West.

INTERACTION

Whenever a unit enters an aboriginal settlement, some form of interaction occurs.

TRADE
When the Europeans first arrived in the Americas, they discovered that trade with the natives could be a very profitable enterprise. The aboriginals had generations of experience trapping beaver, collecting silver, growing tobacco, cotton, and sugar, and they were willing to trade the products of these activities for items produced relatively cheaply in Europe. In Colonization you can trade with the natives very profitably as well. Also, trade is a way of establishing trust between your people and the tribes. By maintaining a friendly, cooperative trade relationship with the Indians, it may be possible to peacefully coexist, and profit at the same time.

ECONOMY
To a large extent, the supply-demand structure of the native economy can be deduced by examining the terrain in which they live. The goods and commodities that the land is capable of producing in the area of an aboriginal settlement are probably abundant. Those the land does not yield are probably in short supply. Logically, natives are willing to trade for things they need, but not for items they have in abundance.

MISSIONARIES
They are very useful emissaries of your colonies. They can influence the mood of the native population with regard to your colonies and the colonies of your European adversaries. They can even incite the aboriginals to attack other European colonies and peoples. Any colonist can be ordained as a missionary, but expert missionaries perform all missionary powers better than non-experts.

HOSTILITIES

An uncredited Colonization player offers the following advice in engaging in battle with native peoples:

This can be a very good method of getting new colonists. First, establish a mission in the village you want to [destroy]. This mission should preferably be with a Jesuit Missionary, but any kind of missionary will do if you have [Father Jean de] Brebeuf in the Congress. Second, after you have [Juan de] Sepulveda in the Congress, but before you add de ]Bartolome de] Las Casas, attack the village. You will get several converts out of this. If you try to coordinate your attacks with attacks on other villages in the same tribe which also have missions, you can get a bunch of converts in just a few turns.

Be careful not to destroy any of the villages, though. As soon as the first one is destroyed, all other missions in that tribe are burned and the natives go on the war path. If you are careful not to destroy the villages, this strategy can be repeated later on with limited success. You will need to do a lot of sucking up to the natives in the interim, though.

Another thing to keep in mind is to avoid attacking and destroying the capitol of any tribe as long as possible. If you manage to provoke the natives to the point where they go on the wa rpath against you, there are only three ways to calm them down. First, you can do a massive amount of sucking up. Give them everything, pay exorbitant prices for their goods, and don't provoke them further. They will calm down eventually. Second, you can get Pocahantas into the Congress. This will immediately reduce all tensions to content. The problem with this is that it's a one-shot deal. Your third option is to attack and destroy the capitol. When the capitol is destroyed the tribe will surrender and go back to being content. This can only be done once per tribe, though. After their capitol is gone, there is no quick solution to a tribe on the warpath.