The calendar plays an important aspect in our lives. It tells us when winter or summer occur. When to plant and when to harvest. It marks certain days to celebrate, commemorate and hold ceremony. Now we usually run on a 365 day calendar, but what if we had two calendars and they weren't the same length. These two calendars are in turn broken into smaller elements which fit together as gears in a machine. Each tooth of each gear means something and as they turn they unfold the destiny of men. Such is the nature of the Aztec calendar. The ultimate random encounter table.
The largest of these set of gears is the xiuhpohualli (year count) a calendar year of 365 days. It is composed of 18 months (metztli) of 20 days each and 5 dark days called nemontemi. The tonalpohualli (day count) is a smaller set. A 260 day ritual calendar comprised of 20, 13 day periods, called trecenas. The xiuhpohualli (year count) and tonalpohualli (day count) spin together giving a year count and a day count for every day in a man's existence. They spin and spin in a cycle that repeats itself every 52 years. A century for the Aztecs sometimes called the calendar round.
The days in the tonalpohualli (day count) each have a name of either an animal or object which indicated what influenced such a day. Some sample name are house, lizard, death, water, grass, and monkey. These days also have a cardinal direction (north, south, east and west). Together these elements carry strong omens and meanings to those born in such days, those wishing to marry, venture on trips, build a house or make war.The cardinal directions were related to gods and held their own symbolism. The East to the God of Rain: Tlaloc, life and fertility. The East was the start of the Sun's travel. The West belonged Chalchihuitl, the Goddess goddess of water, rivers, seas, streams, storms, and baptism. The West also marked the end of the Sun's path. Mictlantecuhtli, the God of Death, Power and Force, owned the North. The South was Xochipilli's, the prince of flowers, god of love, games, beauty, maize and pleasure.
For example, a dire time to travel was the first day of the five western trecena, (1 Deer, 1 Rain, 1 Monkey, 1 House, and 1 Eagle). On those days the dreaded vampire like Cihuateteo would roam road crossings. Stealing children, causing illness and even attacking weary travelers.
Thirteen of these days build up a trecena. There were 20 of these in a tonalpohualli (day count). Each one of these 20 trecenas was associated with a particular deity. These deities held power over these days, sometimes for good and sometimes for ill.
All of this in turn fits into the 365 day xiuhpohualli (year count) calendar, which had it's own days and months! Can you see how the mother all of random encounter tables begins to build up? What fortune will this day bring to the party? Well what god influences the xiuhpohualli month and what god the tonalpohualli trecena and what day is it? Is it a north, east, west or south facing day? Is it a benevolent god? Are we in the dreaded last 5 days of the xiuhpohualli. If so, let's stay in the tavern a few more days.
While two interwinding calendars may be too much for some, a simpler model can be built to add flavor to your setting and particularly your clerics. In your campaign you can set up months and days with each of the important deities, the good and the bad. The meanings for each day. As the gears spin and spin they crank out new paths for the adventure. Giving a good day to travel once then an ill day for a journey at some other time. Calendar dates may put pressure on the party. They have to reach their destination before the end of a certain 13 day period or depart during a certain month. Even small daily omens can help resolve what kind of creature the party will meet and what fortunes lay ahead before sun sets.
If you want to see this in action I strongly recommend the following site. Punch in today's date and read the significance of this day in the Aztec calendar.
For deeper look into the Aztec and Mayan Calendar take a look at the following:
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