Babylonian Calendar Reform 8th c. BC - LexiLine Journal 518

The Encylopedia of World History writes:

"Under Nabonasser (Nabu-nasir, 747-734) an important calendar reform was instituted [in Babylon] in which the monthly lunar cycle was reconciled with the solar year, a standard system still used in the Jewish calendar.

Note also my previous posting on Pharaonic calendar reform.