The ancient world. It spanned from 3000 B.C.E to 476 C.E. What a broad topic under which a lot of information could be found. Here are some places for you to start looking:
100s (Philosophy & psychology):
170.93 Ethics in the Ancient World
180 Ancient, medieval, eastern philosophy
200s (Religion):
292 Classical religion
295 Zoroastrianism
296 Judaism
299.2 Religions of Sumer, Assyria, and Mesopotamia
299.31 Ancient Egyptian religion
299.51 Religions of Chinese origin
300s (Social sciences):
340.093 Law in the Ancient World
370.93 Ancient History of Education
400s (Language):
470 Latin and related Italic languages
480 Classical Greek; Hellenic languages
491.2 Sanskrit
493.1 Ancient Egyptian
500s (Science):
509.3 Science in the Ancient World
520.93 Astronomy in the Ancient World
600s (Technology):
610.93 Medicine in the Ancient World
630.93 Ancient agriculture
700s (Arts & recreation):
709.3 Ancient art
722 Ancient architecture
732 Ancient sculpture
733 Greek and Roman sculpture
800s (Literature):
870 Latin literature
880 Greek literature
892.1 Akkadia, Babylon, Mesopotamia, and Summer - Literature
900s (History and geography):
913 Geography of & travel in the Ancient World
930 History of the Ancient World
