RT Sabado 7

In a vast number of languages, the names given to the seven days of the week are derived from the names of the seven classical planets which were in turn named after contemporary Hellenistic deities. This system was introduced by the Sumerians and later adopted by the Babylonians from whom the Roman Empire adopted the system during late antiquity. In some other languages, the days are named after corresponding deities of the regional culture. The seven-day week was adopted in early Christianity from the Hebrew calendar, and gradually replaced the Roman internundinum. Eight-day and seven-day weeks existed side-by-side until the Emperor Constantine made the seven-day week official in AD 321; thereafter, the seven-day week spread throughout the Roman Empire and eventually through Christian cultures around the world.