The following subject headings are useful if you need ot do research. See if there is a subject heading that looks relevant to your topic. If there is, then click on the link and it will take you to a list of books in that subject area.
BR280 Renaissance. Renaissance and Reformation
D51-90 Ancient history
D101-110.5 Medieval and modern history
D111-203 Medieval history
D135-149 Migrations
D151-173 Crusades
D175-195 Latin Kingdom of Jerusalem. Latin Orient, 1099-1291
D200-203 Later medieval. 11th-15th centuries
D(204)-(475) Modern history, 1453
D219-234 1453-1648