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The Story of Santa Cruz de Terrenate
When the Spanish explorer Francisco Vazquez de Coronado passed through the San Pedro River valley in 1540, he entered a land already inhabited by people for at least 11,000 years. It is for one of the peoples of this area, the Sobaipuri Pima, that the Spanish eventually named the region the Pimeria Alta, or "Land of the Upper Pima." These village-dwellers subsisted on maize, squash, and beans, and wild plants and animals. Their homes, made of brush and mud, were sturdy and well suited to a hot, dry climate. The Pima traded with neighboring tribes, as evidenced by the presence of Glycymeris shell from the Gulf of California and metal objects obtained in the mid-1600s from Spanish settlers farther east.

Thimbles and broken iron scissors excavated at Santa Cruz
These thimbles and broken iron scissors were among the domestic items excavated at Santa Cruz.

By the middle of the eighteenth century, Spain had abandoned its dreams of obtaining gold and silver from the fabled "Seven Cities of Cibola," purportedly located in the upper Rio Grande valley of present-day New Mexico. Neither that area nor northern Sonora had produced the gold and silver of central Mexico and Peru. Denied the riches they sought, the Spanish increased their efforts to christianize the native peoples and to defend their vast empire.

To meet these goals, the Spanish had to overcome several obstacles. Most important, they had to provide military protection to the missions, settlers, and christianized Native Americans who allied themselves with the Spanish. Protection was needed against the western Apache and other tribes who lived a nomadic life-style, hunting and raiding to survive. To provide security on the mission frontier, Spain established a defensive line of presidios. According to the Royal Regulations of 1772, presidios constructed to a standard plan were to be placed forty leagues (one league equals approximately 4,180 meters) apart and linked by regular patrols. "The Line," as it was called, would bar nomadic raiders from New Spain's northern frontier.

Map and artist's rendering of Presidio as it might have looked at completion
Map illustration and artist's rendering of the Presidio as it might have looked at completion.

Putting these events within the context of American history, consider that on July 2, 1775, George Washington arrived in Cambridge, Massachusetts, to take command of the newly established Continental Army. The day before and nearly a continent away, Francisco Tovar completed the muster of his small band of presidial soldiers assigned to Santa Cruz. Fate was to take these two commanders so close in time and duty, down vastly different paths. After years of seemingly hopeless struggle, Washington and his soldiers were to earn the love and acclaim of their countrymen by winning America's War of Independence. Within a year, Tovar and most of his men would lie dead and forgotten in a remote corner of today's Arizona.

The Presidio of Santa Cruz was established on a steep bluff overlooking the San Pedro River on December 10, 1775. By that time, the effects of the European population on the natives, including the Pima of northern Sonora, had already been felt. European disease, notably smallpox, had a devastating impact on the Aztec of the central valley of Mexico. Its spread far outpaced the actual arrival of the Spanish in Pimeria Alta. By then, disease and Spanish slave raiding had drastically reduced the Pima population, making them vulnerable to the Apache, who were themselves being pushed by the Comanche and other tribes westward and southward into Pima territory. Historic accounts reveal that by the time Santa Cruz was built, the Pima had relocated westward to the Santa Cruz River valley because they could no longer effectively fend off the Apache. Archaeologists have identified one earlier period of occupation at the site that ultimately became Santa Cruz--that of the Hohokam tribe, whose culture there dates to the thirteenth century. The Hohokam may be ancestors of the Pima.

Nicolas de Lafora, a military engineer and map maker, recommended that the Presidio of Santa Cruz be established so that the settlers could gather under its protection. The adobe Presidio consisted of a walled compound measuring about 121 varas by 103 varas (one vara equals approximately 83 centimeters), which enclosed a large open plaza. The height of the walls, still under construction in early 1779, varied from 2.5 to 4.5 varas. By this date, approximately 3,592 pesos (about $60,000 today) had been spent on construction. Within the plaza were the commander's quarters, a church, storehouses, settlers' houses, and soldiers' quarters. Eventually over 300 people, including soldiers, their families, and settlers, came to live at Santa Cruz. Historic accounts indicate that the population was multicultural, consisting perhaps of 20 to 30 percent free African blacks and an equal percentage of native peoples--Opata scouts from northern Sonora, Pima from the Tucson area, and other tribes from central Mexico.

Artist's depiction of soldier and settler at Presidio entrance
A soldier and settler in front of the Presidio entrance.

Spain's resources in terms of men, money, and materials could not match the task at hand. For nearly five years, from 1776 to 1780, the Apache posed the same threat to the Spaniards as they had to the Pima. The raiders struck repeatedly at Santa Cruz, capturing horses and cattle and burning houses and crops. Many Spaniards and their Native American allies lost their lives. Two presidial commanders and more than 80 soldiers were killed.

For the soldiers and settlers it was no longer a question of holding "The Line" or of expanding and defending Spain's empire along the northern frontier. Finally, in 1780, after the expenditure of thousands of pesos and scores of lives, the Presidio of Santa Cruz was abandoned.

In 1781, Teodoro de Croix, the new frontier commander, explained that he had abandoned the site because "the terror instilled in the troops and settlers of the Presidio of Santa Cruz that had seen two captains and more than 80 men perish at the hands of the enemies in the open rolling ground at a short distance from the post, and the incessant attacks that they suffered from numerous bands of the Apache, who do not permit cultivation of the crops, who surprise the mule trains carrying effects and supplies, who rob the horse herds, and put the troops in the situation of not being able to attend to their own defense, making them useless for the defense of the province." (Williams 1986)
Santa Cruz remained silent until archaeologists arrived in the middle of the twentieth century to begin excavation.

Setting the World Stage
To set the stage for activities presented on the next few pages, try the following:

  • Compare a map of the world today with a map from the fifteenth century before Columbus made his journey. Explore how the map has changed over the last 500 years with new discoveries, map-making technologies, and shifting political boundaries. Discuss ways the world map may change over the next 500 years.
  • Acquire the earliest map of your hometown. How does it differ from a current map? Examine the spelling of place names and the locations of mountains, rivers, lakes, and other features. Try to find out how these places got their names.
  • Locate a written history of your hometown. Why did settlers come to the area?
  • Trace the major world trade routes in 1492. What goods were exchanged along these routes? Review the economic, religious, and political factors that prompted Columbus to seek a westward path from Europe to the "Indies." (The Spanish wanted to spread Christianity and to gain access to Asian spices, silk, and other products.)
  • Trace the path of Columbus's four voyages. Hypothesize and investigate the types of navigational techniques and devices in use at the time (such as dead reckoning and latitude sailing). Why did Columbus go southward from Spain to the Canary Islands before turning west?
  • Have students identify cities on the same latitude and longitude as their hometown.
  • How did America get its name? Why wasn't it named for Columbus?
  • Discuss Spanish exploration in the Americas. Did they succeed in finding the riches they sought? In christianizing the native peoples?
  • Research how the Spanish divided the Americas into states, provinces, and territories. Did the named provinces have boundaries? How do these territorial boundaries relate to the boundaries of modern countries? Were the names of the Spanish provinces the same as current names? Were the province, territory, and city names all in Spanish, or did the Spanish sometimes adopt existing place names?
  • Using historic accounts by missionaries, soldiers, and explorers, examine the Spanish view of the native population. What did the Spanish bring with them that changed the lives of these people? (They brought Christianity, foreign disease, horses, cows, pigs, chickens, wheat, oranges, and sugarcane, for example.)
  • How did the native populations view the Spaniards? What did the natives share with the Spaniards? (They introduced the Europeans to maize, potatoes, beans, squash, pineapples, turkeys, and tomatoes.)

Designs found on local red-on-brown pottery
Pottery designs on local Red-on-brown pottery

 Artifacts in Context
How did archaeologists and historians determine that both Native Americans and Spaniards lived at this site during two periods of occupation--one almost 900 years ago, the other 200 years ago? Just like detectives gathering clues, archaeologists who excavated Santa Cruz examined the objects that people made (artifacts) and where they left them (context) to piece together the story.

Because the excavation of a site destroys it, archaeologists carefully record on paper the location of all objects and structures as they are uncovered. Future researchers can study a site they've never seen if good notes and maps are made of the excavation. Recording the context is the key to interpreting a site from archaeological records. The disturbance or removal of "clues" makes an archaeologist's job more difficult, if not impossible.

Archaeologists maintain context with a grid, a Cartesian coordinate system set up using a surveying instrument (usually a transit or alidade), measuring tapes, and wooden stakes.

A site is measured in squares, usually one or two meters in size. Wooden stakes mark each square corner, and each square has a unique designation--the coordinates of one of its corners. The coordinates indicate the distance of a given point north, south, east, or west of the site datum (0,0). Everything found within a particular square is identified by that square's number, and every object can then be tied back to its place in the site.

Map showing routes of explorers from 1519 to 1776 

Try these activities to demonstrate the importance of context.

  • Divide the class into groups of five or six students and assign each group a different number. The groups then pick a place, such as a hospital operating room, a kitchen, or a hardware store, and decide what objects in the room make it distinctive. Then each student writes one clue on an index card, for a total of five or six clues per group. Each card also has the group number written on one side. The stack of cards from each group is passed to another, until every group has seen every stack and tried to guess each room's function. Students can play additional rounds, making it more challenging by including fewer clues per round until only one clue is left. This demonstrates the type of problem faced by archaeologists when artifacts, or clues, are removed from a site.
  • Have each student bring in a brown paper bag containing 5-10 personal items. They should give their unlabeled bags to the teacher, who distributes them to the class, making sure that no one gets his own bag. Students then open the bag and infer the behavior or personality of the anonymous owner. They might be able to guess who owns the bag. Each student presents the results of his "study" to the class. They will realize that they can infer the bag's owner only because the artifacts are in context with each other.
  • On the playground, establish a grid of five-meter squares using measuring tapes, stakes, and string. Have students record the grid location of features on the playground. Using graph paper, explain that each square on the paper corresponds to a square on the ground. By labeling the grid, students can create a map of the playground by plotting the location of their recorded features on the graph paper.

Objects As Evidence
Using shovels, trowels, screens, and measuring tapes, archaeologists uncovered the Santa Cruz site. Each artifact was carefully measured and recorded as it was found. By making observations about the artifacts, archaeologists were able to make inferences about the people who used them.

One object found at Santa Cruz was a ceramic candlestick. The candlestick, made of local Sobaipuri Plainware pottery rather than the usual bronze or iron, represents the mixing of the Spanish and Pima cultures. The Spanish may have obtained such artifacts from the local native populations or manufactured the items themselves, or a combination of the two.
Native Americans did copy certain Spanish forms, such as soup plates, lipped plates, and cups. Ninety percent of the artifacts recovered by archaeologists at Santa Cruz were of Native American "origin." Historians tell us that the Spanish did not begin to mine iron in the Americas until the late eighteenth century. Before that time, they imported iron in bulk form from Spain. The scarcity of iron may have forced the Spanish to rely on native-made wares, such as pottery and stone tools.

Artist's depiction of three sherds of pottery types and a candlestick found at Santa Cruz

Objects excavated by archaeologists at Santa Cruz, including three sherds of commonly found pottery types (from top, Majolica, Tanque Verde Red-on-brown, and Mimbres Black-on-white) and a pottery candlestick. The candlestick, made of local Sobaipuri Plainware rather than the usual bronze or iron, represents the mixing of the Spanish and Pima cultures.

Artist's rendering of Native American cremation pit  Artist's rendering of Native American dwelling
Artist's renderings of Native American cremation pits and dwelling.

Classifying Objects
In excavating Santa Cruz, archaeologists found thousands of objects. The site contained hundreds of pottery sherds varying greatly in appearance. Rather than comparing every pottery sherd to every other pottery sherd, archaeologists classified them by such attributes as surface decoration and color, clay body, and firing technique. Pictured above are sherds representing three of the basic pottery types into which archaeologists grouped sherds found at Santa Cruz.

One unusual and easily classifiable type found there is manure-core temper variety. Temper is a substance mixed with clay to prevent a pot from breaking during firing. The core of this manure-tempered ceramic type is dark as a result of using organic cow dung, and often particles of hay fed to the cows can be detected in the sherds under a microscope. Because cattle were not introduced into Pimeria Alta until the late seventeenth century, we know this ceramic type was made after that time.

Try the following classification activities with your students.

  • Divide the class into groups of four or five and give each group a kit that contains about 20 familiar objects, such as bolts, string, rocks, paper clips, and cloth. Have each group organize the objects into categories, using their own classification scheme. When everyone is finished, ask each group to explain what attributes they used to place an object in a certain category--shape, color, or type of material. Ask the class how its scheme would change if certain items or classes of items (say, all red things) were removed. Point out that the removal of artifacts, such as arrowheads, from a site alters the classification and hence the questions that can be answered from the data.
  • Obtain 5-10 ceramic vessels from a secondhand store for each group of students. Stoneware is recommended, since it typically breaks into a few dozen pieces, while other types of ceramics may shatter into literally thousands of pieces. You may need to experiment. Two of the vessels are to be the same--two cups, for example. The remaining vessels should be different in surface glazing and shape. Break all the vessels and put all of the assemblage pieces together in a shoebox or paper bag. Keep in mind that broken pottery will have sharp edges, so consider the appropriateness of this activity for your class. Students work in groups of three to five to sort and classify the sherds into different categories. When they have finished sorting, ask them how they separated the pieces. By color? Shape? Both? Ask them to infer how many separate vessels are represented and explain how they made the inference.
    Next have the students reconstruct the vessels using white glue. Were they right about the number of vessels?
  • Pottery fired in an oxidizing atmosphere (oxygen freely available) looks distinctly different than pottery fired in a reducing atmosphere (oxygen limited during the firing process). If you can obtain samples of the two types, consider exploring with your students why the same pottery will achieve two different effects when fired in these two different atmospheres.

Archaeologists and historians attempt to establish the age of sites, artifacts, and events so that they can be placed in chronological order and reveal the story of the past.

We know several ways of determining the age of an object or site. One of the simplest means is based on the law of superposition--objects at the bottom of a buried site are the oldest, and those at the surface are the youngest. While this method establishes relative dates of older and younger artifacts, it does not establish an absolute calendar date. Digging or other disturbance of a site prevents archaeologists from reading its chronology.

At Santa Cruz, two primary methods were used to establish age: historic records and cross-dating. Cross-dating indirectly establishes a date based on styles of artifacts. Artifacts of a distinct style that have been dated at one site can be used to date objects of a similar style found at another site. A modern analogy is automobiles; one would not mistake the style of a car made in the 1920s with one made in the 1990s.

A style of ceramics found at Santa Cruz in association with the Hohokam occupation is known as Mimbres Black-on-white. Archaeologists could date the Mimbres Black-on-white pottery found at Santa Cruz because the same style had already been dated at another site. This pottery type, which originates in the area that is now southwest New Mexico, has been dated there to 1100-1250.

Try this activity to let students conclude on their own that chronology is important.

Have students write on strips of construction paper 10 or 12 significant events in their lives. These events should not have obvious time links, such as "my eighth birthday party". They should then scramble their strips and exchange them with another student, who must try to lay the strips out in correct chronological order. Discuss as a class or team: Were you able to reconstruct the timeline correctly? Why or why not? It is difficult, sometimes impossible, to reconstruct a story if the order of events is not known. Connect this activity to archaeological sites by stressing how archaeological data are usually impossible to place in chronological order if people have removed artifacts.

 Historical Records
Our earliest knowledge of the land and peoples of the area can be glimpsed in the diaries, reports, and maps prepared by Spanish missionaries, such as the Jesuit Father Eusebio Francisco Kino who came to the San Pedro in the late seventeenth century. Like any source of information, historians must critically evaluate these documents. Kino named the native settlement that he encountered, at the location of present day Santa Cruz, Quiburi. Later scholars who used his writings considered the simple living structures found at the Presidio to be the remains of this early village. Today, however, scholars interpret these remains as the first living quarters erected by the Santa Cruz soldiers. The location of "Quiburi" remains a mystery.

Other documents, such as Lafora's diary, provide insights as to why a defensive post was needed along the San Pedro. The Royal Regulations of 1772 tell us about the construction of the posts, about the weapons, pay, and duties of the officers and soldiers at the forts, and about the siting of Santa Cruz de Terrenate. Muster rolls, such as that prepared by Captain Tovar, tell us about the soldiers themselves, such as the number present, their ages, origins, and the sociocultural composition of the Spanish frontier garrisons. Inspection reports of arms and other supplies suggest the state of morale and readiness of the defenders. Teodoro de Croix's letter to his viceroy gives us a vivid and painful picture of the conditions at the Presidio.

To better understand how historians use historical records, photocopy and distribute the muster of soldiers prepared by Captain Francisco Tovar on July I, 1775, and have students answer the following questions:

  • What was the average age? (33.6 years)
  • What percentage of the troops were of Hispanic descent? Of other descent? (77 percent unmixed Hispanic, 23 percent other ancestry)
  • Why do you think these natives served as allies of the Spanish? (They allied themselves with the Spanish or other European colonizers for a variety of reasons. Some saw a military alliance with the Spanish as a means to continue warfare against their traditional enemies with the advantage of additional numbers of fighters and weapons. Others saw certain items of European material culture as desirable or superior to their own products and so they allied themselves with Spain in order to secure them.)
  • What does this information tell you about Spanish policies and conditions on the frontier? (The racial integration of the presidial garrison points out Spain's open-mindedness on cultural issues. More than any other European colonizing power, Spain sought to integrate Native Americans into its colonial society. For example, interracial marriages were accepted, and children of such marriages could advance in Spanish institutions such as the military.)
  • On a map of Mexico, locate the provinces in which these men were born.

To conclude your unit, have students reassemble their personal "artifacts" and create written materials that tell about themselves. Let the children exchange these and write histories of one another based strictly on the "evidence" provided. Read these aloud. Afterwards, discuss with students the strengths and limitations of both historical and archaeological types of evidence in helping us unravel the stories of the past.



What a Coin Can Tell Us

Both sides of Spanish coin found at Santa Cruz

Archaeologists found this Spanish coin at Santa Cruz. The study of coins, called numismatics, tells archaeologists and historians much about the past. A variety of techniques, ranging from simple to complex, can glean this information.

By simply observing a coin's symbols, or iconography, we can learn about a nation's leaders, national events, or beliefs. Coins bearing dates help archaeologists to date a site. Using the principle of terminus post quem (the date after which), a site can be dated by the newest object found there.

Sophisticated techniques answer more complex questions about the past, such as coinage standards and metallurgical skills. For example, a nation may periodically debase its currency, using poorer metals or increased percentages of them, when facing periods of political or economic stress. X-ray fluorescence analysis using a spectrometer can establish a quantitative indication of the metals comprising a coin. The technique measures the amount of energy each metal in the coin emits when bombarded by X rays. This illustrates how the relative amounts of metals in coins have changed over time.
The specific gravity of a coin, or the ratio of its mass to that of an equal volume of water, can also be used to measure the coin's purity in gold or silver.
Discuss with students the concepts of observation and inference.

Ask students to determine which of the following statements about the coin on this page are observations and which are inferences.
The date 1768 appears on the coin. (observation)
The Spaniards could read and write. (inference and observation)
Pictures of a lion and a castle appear on the coin. (observation)
The Spaniards could extract and process metals. (inference)

  • Have students work together to design a coin that features values important to them. Exchange designs and have student groups write statements of observation and inference about another group's coin design.
  • Translate the Latin words on the coin into English. What do they signify and why was Latin used?
  • Research how scientists find gold and silver deposits.
  • Review the process of decomposition and the rates at which various materials decompose. Discuss the effect of climate and soil on the process of decomposition. Wet, acidic, sandy soil quickly attacks metal objects. Dry climates preserve certain types of remains, such as textiles.
  • Discuss how our interpretation of the past might be skewed if people used objects that deteriorated quickly.
  • Research the cultural heritage of your community to learn what various groups have contributed in terms of language, customs, values, religion, building styles, art forms, government, education, and occupations.

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