Julius Caesar introduced the Julian calendar as a reform of the Roman calendar, which was based on the lunar cycle. It was established in 45 BC and was used for thousands of years.
Based on the solar year, with a cycle of three years of 365 days followed by a year of 366 days (leap year). The year began on January 1, and the vernal equinox was standardized on March 21.
The Julian calendar became the predominant calendar in the Roman Empire and most of the Western world for over 1,600 years. It was the precursor to the Gregorian calendar we use today. These systems removed most of the world away from lunar observance of calendaring.