Heilbrunn Timeline of Art History (Metropolitan Museum of Art)Includes overviews and descriptions of key events. Note essays and related keywords. Note also the suggested bibliography ("Further reading") listed under each essay -- these books and articles may help you with your research.
"Chronological, geographical, and thematic exploration of the history of art from around the world, as illustrated especially by the Metropolitan Museum of Art's collection." Extends from prehistory to 1600 AD and will continue to expand in scope & depth.