The American Religious Ecologies project is creating new datasets and visualizations for the study of American religious history. Datasets and visualizations, though, are means to the end of creating historical interpretations that advance our knowledge of American religious history. In particular, we are seeking to understand American religion through the lens of religious ecologies. The term ecology of religion encourages us to look at the interactions of religious groups with one another, as well as their interactions with their geographic, political, cultural, and social environments. Using this map we can see ways, even on this large scale, in which Roman Catholicism has interacted with its larger geopolitical environment. Indeed, scale is part of the point: while most studies of religion that take an ecological framework have focused on the scale of the street, the block, or the city, the concept is also useful at larger scales.2
There are three things we can observe about religious ecologies at this continental scale.
The first thing to note is the transnational scope of Roman Catholicism. Perhaps this point is obvious in the case of a global church like Roman Catholicism, but the point is made more striking when depicted in geographical space. Without denying the significance of the nation for understanding religious developments, the boundaries of the nation-state are only sometimes the appropriate boundaries for the study of a religious tradition.
Take, for instance, the map in 1789, the first year for which the background political boundaries displayed on the map are even approximately correct.3 That year saw the establishment of the Diocese of Baltimore, the first Roman Catholic diocese in the newly formed United States. The founding of a new nation enabled the creation of a new diocese, even if the presence of a Roman Catholic diocese in the British-controlled province of Quebec, formerly a French colonial possession, had been at issue in the lead-up to the American revolution. But the presence of institutional Roman Catholicism on the continent was hardly limited to those two dioceses. By 1789, Roman Catholic dioceses had been established for nearly three centuries on the continent. The first two were the diocese of San Juan and the diocese of Santo Domingo, now in Puerto Rico and the Dominican Republic. In 1789, there were two dioceses north of the Rio Grande, but there were ten in the territory that became Mexico and four in the Caribbean. The institutional hierarchy of the Roman Catholic church was thus well developed on the continent long before the founding of the United States and Canada as nation states.