Tamales a potted history.
A tamale or tamal is a traditional Latin American dish made of masa (a starchy dough, often corn-based), which is steamed or boiled in a leaf wrapper. The wrapping is discarded before eating. Tamales can be further filled with meats, cheese, vegetables, chilies or any preparation according to taste, and both the filling and the cooking liquid may be seasoned.
Tamales were one of the staples found by the Spanish Conquistadors when they first arrived in Mexico and were soon widely spread throughout their other colonies. Tamales are said to have been as ubiquitous and varied as the sandwich is today.
Tamales originated in Mesoamerica as early as 8000 to 5000 BCE. Aztec and Maya civilizations as well as the Olmeca and Tolteneca before them used tamales as a portable food, often to support their armies but also for hunters and travelers. There have also been reports of tamal use in the Inca Empire long before the Spanish visited the new world.
The diversity of native languages in Mesoamerica led to a number of local words for the tamal, many of which remain in use.
In Mexico
In Mexico, tamales begin with a dough made from nixtamalized corn (hominy), called masa, or a masa mix such as Maseca, and are generally wrapped in corn husks or plantain leaves before cooking, depending on the region from which they come. They usually have a sweet or savory filling and are typically steamed until firm.
Few countries have such an extensive variety of tamales as Mexico, where they're considered one of the most beloved traditional foods. Almost every region and state in the country has its own kind of tamal. It is said that there are between 500 and 1000 different types of tamales all around the country. Some experts estimate the annual consumption in hundreds of millions every year.
Tamales are a favorite comfort food in Mexico, eaten as both breakfast and dinner, and often accompanied by hot Atole or Champurrado, maize-based beverages of indigenous origin. Street vendors can be seen serving them from huge, steaming, covered pots (tamaleras).
In Mexico City, the tamal is often placed inside a wheat bread roll to form a torta de tamal (also called guajolota), substantial enough to keep a person satiated until Mexico's traditional late lunch hour.
The most common fillings are pork and chicken, in either red or green salsa or mole. Another very traditional variation is to add pink colored sugar to the corn mix and fill it with raisins or other dried fruit and make a sweet tamal (tamal de dulce). There are commonly a few "deaf", or filling-less, tamales (tamal sordo), which might be served with refried beans and coffee.
The cooking of tamales is traditionally done in batches of tens if not hundreds, and the ratio of filling to dough (and the coarseness of the filling) is a matter of discretion.
Instead of corn husks or plantain leaves, banana leaves are used in tropical parts of the country such as Oaxaca, Chiapas, Veracruz, and the Yucatán Peninsula. These tamales are rather square in shape, often very large— 15 inches (40 cm) or more— and thick; a local name for these in Southern Tamaulipas is Zacahuil. Another less-common variation is to use chard leaves, which can be eaten along with the filling.
Tamales became one of the representatives of Mexican culinary tradition in Europe, being one of the first samples of the culture that the Spanish conquistadors took back to Spain as proof of civilization, according to Fray Juan de Zumarraga.
Today, tamales are often eaten during festivities, such as Christmas, the Day of the Dead, Las Posadas and Mexican Independence Day.
Tamales elsewhere in Latin America
Cuba
In Cuba, before the 1959 Revolution, street vendors sold Mexican-style tamales wrapped in corn husks, typically made without any kind of spicy seasoning in order to accommodate the milder Cuban taste. The fact that Cuban tamales are identical in form to those made in Mexico City suggests that they were brought over to Cuba during the period of intense cultural and musical exchange between Cuba and Mexico, between the 1920s and 1950s.
A well-known Cuban song from the 1950s, "Los Tamalitos de Olga," (a cha-cha-cha sung by Orquesta Aragón) celebrated the delicious tamales sold by a street vendor in Cienfuegos. A peculiarly Cuban invention is the dish known as tamal en cazuela, basically consisting of tamal masa with the meat stuffing stirred into the masa, then cooked in a pot on the stove to form a kind of hearty cornmeal porridge.
Corn-husk wrapped tamales are also popular in southeastern Cuba.
Tamales in Trinidad and Tobago, the Dominican Republic and Puerto Rico are known as pasteles. The dough is usually made of green plantains, yautia (dasheen) or yuca (cassava) and green bananas. The wrap is primarily plantain or banana leaves. They also have "guanime", or "guanimo" in some areas. It is made with yellow cornmeal, coconut milk and a pinch of sugar, wrapped in a banana leaf, and boiled. There is a version with filling called guanimes rellenos. This filling may be ground beef, chicken or pork.
Central America
In Belize, El Salvador, Guatemala, Costa Rica, Honduras, Nicaragua and Panama they are wrapped in plantain leaves. The masa is typically made out of maize (non-sweet corn), such as what is known as feed corn in the U.S. The corn typically eaten in the U.S. on the cob (sweet corn) is called elote. Guatemalan cuisine is known in particular for their hundreds of varieties of tamales, popular varieties, include tamales de gallina (chicken), tamales dulces (sweet), and tamal de elote (in Costa Rica, the name can also refers to a type of corn pastry). In Guatemala a variety of tamal is called "Tamal Colorado," which has a chicken, or pork filling, a prune, capers, an almond, red bell pepper, and masa with tomato. (hence the "colorado," which means colored).
The tamal is a staple in Belize, where it is also known by the Spanish name bollo. Nicaragua has a large form known as Nacatamales.
In Guatemala, Belize, El Salvador and Honduras, there are tamales without filling which are served as the bread or starch portion of a meal:
    * Tamal de elote (made with yellow corn, sometimes with a sweet or dry taste)    * Tamal de chipilín (made with chipilín, a green leaf)    * Tamal blanco (simple, made with white corn)
During Christmas holidays, tamales of corn flour are a special treat for Guatemalans. The preparation time of this type of tamal is long, due to the amount of time required to cook down and thicken the flour base.
In Panama, tamales are considered one of the main national dishes. The Panamanian tamal is fairly large. The most common fillings are chicken, raisins, onions, tomato sauce, and sometimes sweet peas. Pork is also used. Another variation is tamal de olla, which is cooked in a pot and then served directly onto plates. Tamales are usually served for all special occasions, including weddings and birthday parties, and are always found on the Christmas dinner table.
South America
Tamales are found in the north of Argentina (the provinces of Jujuy, Salta and Tucumán). Tamales Salteños are made with shredded meat of a boiled head of a lamb or pork and corn flour wrapped in "chalas". Tamales Jujeños use minced meat and corn and red peppers.
Another version is called humita. It is found in Peru, Argentina and Chile. It can be salted or sweet. Sweet ones have raisins, vanilla, oil, sugar. Salty ones can be filled with cheese (queso fresco) or chicken. Humitas are cooked in the oven or in the pachamanca. Humitas are not tamales by Peruvian and Argentine standards. In Chile the food known as humitas is almost identical to the tamale.
Peruvian and Bolivian tamales tend to be spicy, large and wrapped in banana leaves. In Lima, common fillings are chicken or pork, usually accompanied by boiled eggs, olives, peanuts or a piece of chili pepper. In other cities, tamales are smaller, wrapped in corn husks and use white corn instead of yellow corn.
In Brazil, there are two kinds of tamales known as "pamonha", which can be salty or sweet and is usually served warm, and "curau", which is sweet and is usually served cold.
In Venezuela tamales are called Hallacas. They are wrapped in plantain leaves and filled with stewed pork, raisins and olives. They are traditionally eaten for Christmas. Also the Venezuelan "bollos" are similar to the tamal, wrapped in corn husks, filled with hot peppers or plain, and eaten as a side dish.
In Colombia, they are wrapped in plantain leaves. There are several varieties (including most widely known tolimense as well as boyacense and santandereano). Like other South American varieties, the most common are very large compared to Mexican tamales — about the size of a softball — and the dough softer and wetter, with a bright yellow color. A tamal tolimense is served for breakfast with hot chocolate, and may contain large pieces of cooked carrot or other vegetables, whole corn kernels, rice, chicken on the bone and/or chunks of pork. A related food is the envuelto or bollo, which is often made of yucca flour cooked in a corn husk, and resembles a typical Mexican tamal more closely but has simpler fillings or no filling at all.
Ecuador has a variety of tamales and humitas; they can be filled with fresh cheese, pork, chicken or raisins. Ecuadorian tamales are usually wrapped in corn husk or achira (aka Canna) leaves.

United States
Tamales have been eaten in the United States since at least 1893, when they featured at the World's Columbian Exposition.[2] A tradition of roving tamal sellers was documented in early 20th century blues music.[2] They are the subject of the well-known 1937 blues/ragtime song They're Red Hot by Robert Johnson.
While Mexican-style and other Latin American-style tamales feature at ethnic restaurants throughout the United States, there are also some distinctly regional, indigenous American styles.
Semi-sweet tamales, wrapped in banana leaves and called guanimes, are found in Puerto Rico.
In the Mississippi Delta, African-Americans developed a spicy tamal made from cornmeal (rather than masa), which is boiled in corn husks.
In Chicago, unique tamales made from machine-extruded cornmeal wrapped in paper are sold at Chicago-style hot dog stands.