The two libraries in 2012 announced a four-year project to digitize some of the most important works of their collections of Hebrew manuscripts, Greek manuscripts and early printed books.
Among the first up on the site Tuesday, are the two-volume Gutenberg bibles from each of the libraries and a beautiful 15th-century German bible, hand-colored and illustrated by woodcuts.
The 2 million pound ($3.3 million) project is being funded by the Polonsky Foundation, which aims to democratize access to information.
The Vatican Library was founded in 1451 and is one of the most important research libraries in the world. The Bodleian is the largest university library in Britain.