Canadian Historic Sites: Occasional Papers in Archaeology and History No. 6

The Excavation and Historical Identification of Rocky Mountain House

by William C. Noble

Techniques and Method of Excavation

As with the excavation of all historic sites, the excavation of Rocky Mountain House involved and combined the goals of historical and archaeological research techniques and methods. Both disciplines, history and archaeology, overlap in this instance and have a common objective — a mutual contribution to increased knowledge. Briefly stated, the objectives for excavating Rocky Mountain House were three-fold: (1) to recover the architectural pattern of the remaining physical features of the fort together with associated artifacts; (2) to make a positive historical identification of the fort and its integral structures and (3) to ultimately study the position and function of the fort in its wider context of the fur trade and exploration in western Canada.

Archaeology contributed the techniques and methods instrumental to realizing the first objective. Historical identification is realized by comparing and evaluating the similarities or dissimilarities between written descriptions of the fort and what was actually found upon excavation. The realization of this second objective is clearly a mutual product and is only as sound as the historian's and archaeologist's ability to interpret their raw data. The third objective falls primarily within the realm and scope of the historian. Anthropologists, however, wishing to study the effects and policies of the fur trade as they affected the indigenous Indian populations, can also contribute from the point of view of ethnohistory and studies of culture change.

Techniques of Excavation

At Rocky Mountain House two techniques of excavation were employed. The first, used by Dr. Richard G. Forbis in 1962, involved the initial systematic testing of the site. This was accomplished by excavating a system of two-foot wide trenches across the main axes of the site (Fig. 3). Thus the limits of the exterior walls of the fort and details of some of the interior structures were recorded. Pickets of the palisade walls were well-preserved and clearly distinguishable. Soil excavated by trowel was put through a screen to ensure recovery of artifacts, and subsequently the excavated area was mapped.

In 1963, total excavation of the site necessitated a larger scale technique and a system for rapid and accurate recording of the field data. Accordingly, a grid system of 40-ft. squares, each called a sector, was established over the site with the use of a transit. Each sector was given an alphabetical label and further divided into four clockwise numbered quadrants, each 20 ft. square. The datum point of the grid, CoDo, was at the northeast corner of the excavation at a point established the previous year by federal surveyors.

Excavation proceeded by quadrants. A mine detector was helpful in locating metal objects and areas of ash beneath the turf prior to the opening up of each unit.

As the site had previously been ploughed, the top four to six inches of turf and sandy soil were removed by shovel. Disturbance was not found to be deep, generally extending only to a six-inch depth. After the removal of the upper levels of turf, trowels were used to clean and expose the buried subsoil features of the fort. Pits were numbered with arabic numerals and building structures with roman numerals. All pits were cross-sectioned in excavation and the contents screened for artifacts. Scale diagrams were then drawn of their stratigraphic profiles and these diagrams supplement the photographic record of the fort's features.

Coordinate tape measurements were made to record the salient features of the fort. Positions of all posts, pits and other distinguishable features were recorded by measuring their distances from any two of the four corner pegs bounding a quadrant. The features for each quadrant were then plotted by compass triangulation from the permanent record of measurements. The over-all ground plan of the site (Fig. 3) is a composite of the quadrant diagrams. Figure 2 is a contour map of the site with the quadrants labelled.

Methods of Analysis

Analysis techniques applied to the architecture, soil features and artifacts from Rocky Mountain House are primarily descriptive with comparative references when available. Each of the various features and artifacts is first considered in terms of its description and associations, and then with broader distributions over the various sectors of the fort and with similar specimens from other sites. This procedure has the advantage of fully presenting the raw data in a form useful for present and future comparisons with material from other excavated western forts. Also, the distributional studies highlight configurations or patterns, if present, both on the site and across the country.