Subject Areas (By Place & Date of Publication)

Subjects by Place of Publication

Chart 6.1: Top 15 Subjects by Region of Publication

The chart below shows the top 15 subjects and how many items were published about those subjects in specific regions of the world. This visualization indicates that a majority of the materials about these top 15 subjects were published in Europe (75.69%). This confirms the observation made in section 4, regarding the place of publication. One exception to this observation is that items about American History were primarily published in the United States. The largest subject area covered by the collection is Christian Denominations, with the majority published mostly in Europe closely followed by the United States. The second most prevalent subject area covered is Theology, followed by The Bible, and then General Christianity. The collection also has holdings of a considerable number of books in Greek and Latin Language and Literature, European History, Ethics, Philosophy, and Religion.

Chart 6.2: Top 15 Subjects by Country of Publication

While chart 6.1 visualized subjects by region, the series of maps in chart 6.2 depicts the same information zoomed in from a country perspective. This story map shows the top 15 subjects across the tabs at the top of the chart. Clicking on each of the subject tabs above the chart shows how many items were published in each country about that specific subject. The darker the color, the higher the number of items published in that country. Hovering above each country will show the name of the country, broader subject term, narrower subject term, and the number of items published in that country. As demonstrated in chart 6.1 the majority of the materials about Christian Denominations were published mostly in Europe followed by the United States. Similarly materials related to the Theology subject area were published mostly in Europe, followed by the United States. A few books about Theology were also published in Canada and Asia--specifically in India, China, Japan, and Indonesia. As for Biblical Studies or works about The Bible--most were again published in Europe followed by the United States. However, a few books about The Bible were also published in Brazil, South Africa, Turkey, Israel, Vietnam, the Philippines, and Australia.

Subjects by Date of Publication

Chart 6.3: Top Subjects by Publication Date

The charts in the tabbed display below show changes in the subject composition of the collection over time. The first two tabs depict top-level subjects (the broadest subject categories, derived from the main classes of the Library of Congress Classification), first as a heat map and then as a bar graph. (For the sake of legibility, only the top 10 most common high-level subjects are shown.) In both charts, some classes (like Religious Studies and Language & Literature) remain a consistent part of the collection over time; Law has a clear peak in the 16th and 17th centuries, but drops off in the later part of the collection; History of the Americas, Fine Arts, and Education become more frequent in the 19th and 20th centuries.

The third and fourth tabs provide a more detailed view of subject data over time, using the most commonly occurring second-level subjects based on Library of Congress Classification subclasses (these are the more granular subjects shown in Charts 5.2-5.2.3). The data is visualized first as a heat map, and then as a bar chart. Both charts show that Christian Denominations, the most populous sub-category, is a major component of the collection throughout, but other subclasses show more variation over time: Ethics (like Law in the Top-Level diagram) has a clear peak in the 16th and 17th centuries, but drops off later on; there is also a noticeable uptick in the British History class in the first half of the 19th century, and in the Middle Eastern/North African languages class in the late 19th to early 20th century.

Chart 6.4: Detailed Subjects Over Time

This chart provides another way of visualizing changes in top-level and second-level subject data over time. Each tab presents a “snapshot” of the subject makeup of the collection within a given century. Each bubble in the chart represents a different second-level (subclass) subject category; the bubbles are color-coded to reflect the broader class that each subclass is part of, making it possible to get a sense of the distribution of both top-level and second-level subject categories in each century. In each tab, you can also click on the relevant subject class in the legend at the right to highlight all the members of that class. (Note: Unlike the previous visualizations in this section, which are filtered to show only the top subject categories, this visualization shows all the classes and subclasses present within each century.)

Subjects by Date and Place of Publication

Chart 6.5 Top Countries of Publication by Subject and Publication Date

This chart shows how subject data changes over time in the top 10 countries of publication found in the collection, making it possible to compare overall levels of output by different countries. Within the row for each country, publications are broken up by century and color-coded to show the number of items in each top-level subject category.

Chart 6.6: Percentage View of Top Countries of Publication by Subject and Publication Date

This chart depicts the same data as the previous chart, but represented as a series of pie charts instead of bar graphs. Each pie on the chart shows the subject breakdown (in terms of percentage) for a country within a given century. Whereas the bar graphs above are useful for comparing absolute numbers of records, the pie charts are good for comparing, relatively, what percentage of a country's total output is taken up by a given subject, at different points in time. From these charts you can see that the United States and the United Kingdom have a higher percentage of non-religion subjects from the 18th century onwards; the Netherlands has a high percentage of non-religion subjects, too, while the output from Italy and Spain is primarily religious throughout.

Chart 6.7: Top Subjects by Place and Date of Publication

The two charts in the tabbed display below provide another way of viewing how subjects break down by place and date of publication, the first focusing on top-level subjects, the second focusing on the more granular second-level subjects. Both are limited to the top ten countries of publication, and the top ten subject classes and subclasses (respectively). To see when and where works on a particular subject were published, click on the subject in the legend at the right.

In the Top-Level diagram, we can see that Religious Studies/Theology (the most common top-level subject category) is present in almost every part of the diagram, but there are also places and times when other subject categories become more prominent (for example, Language/Literature in Netherlands around 1700; or History of the Americas in the United States in the 19th century). Similarly, while blue (representing the Christian Denominations subclass) dominates much of the Second-Level Subjects diagram, clicking on the green Ethics headings shows concentrations of publications in that area in Belgium, France, and Germany in the 17th century, followed by a slightly later peak in Italy in the 18th century (and a secondary peak in Germany around the same time).