To find information and context about your chosen work and composer, the following resources will be helpful:
For help identifying composers from the appropriate period, refer to the Timelines of Composers.
Some shorter pieces may be in recorded collections which may not be retrievable by composers. In these cases, use Library of Congress Subject Headings (LCSH) to find useful subject headings, such as Motets. Don't forget about the standby "catch-all" subject headings used for collections, such as Vocal music, Instrumental music, Keyboard music, and so on. You can add time periods, such as 15th Century, for increased specificity.
Many scores may also be found in collections, especially those that are complete works and collected editions.
To learn more about complete works and collected editions, please refer to the Scholarly Editions section in this guide.