The first nation to create a one-year calendar were the Mayans.
They built a giant pyramid named Chichen Itza, which has four stairways of 91 steps. Together all the stairs total in 365 steps which stand for the days in one year.
The calendar was adopted by the Aztecs and Toltec, who changed the names of the months and weeks.
The Mayan calendar uses three different dating systems: the Long Count, the Tzolkin, and the Haab. Only the Haab has a direct relationship to the length of the year. The Haab is a calendar of the Mayans that consisted of 18 months of 20 days each and five extra days called the Uayeb. This calendar was 365 days long.
My Mayan date of birth is: