Alphabetical Subject Indexing: A Historical Overview

The question asks about the historical period when alphabetical subject indexing became a more common and organized practice. Alphabetical subject indexing is a method used to organize information based on subjects arranged in alphabetical order. This helps users find relevant materials more easily.

Analyzing the Options for Widespread Indexing

Let's examine the historical context of the given options:

• Late 19^th century: This period (roughly 1870s-1890s) saw significant growth in publishing, education, and the establishment of large public and academic libraries. The need for systematic ways to organize the increasing volume of knowledge became critical. Innovations in cataloging and indexing emerged during this time, including more structured approaches to subject indexing using alphabetical lists. Thinkers like Charles Ammi Cutter were developing standardized systems.
• $13^{th}$ century: This was the High Middle Ages. While libraries existed, primarily in monasteries and universities, their collections were smaller, and indexing methods were often based on simpler classifications or author/title arrangements, not widespread systematic subject indexing.
• Early $21^{st}$ century: This is the modern era, characterized by digital information and sophisticated search engines. While alphabetical subject indexing is still used, its *introduction* and widespread adoption happened much earlier. This era represents the refinement and digitization of indexing, not its initial widespread introduction.
• $15^{th}$ century: This marked the beginning of the Renaissance and the invention of the printing press. Although the printing press drastically increased the number of books, systematic subject indexing was still in its infancy. Early printed books sometimes had tables of contents or rudimentary indexes, but the practice wasn't yet widespread or systematic in the way it later became.

Conclusion on Indexing Practices

The Late 19^th century is recognized as the time when forces like industrialization, increased literacy, and the library movement converged, demanding and fostering the development of more systematic and widespread indexing techniques, including alphabetical subject indexing. The systems developed then laid the groundwork for modern information organization.