Aztec Tonalpohualli
The 260-day count, trecenas and the codices.
Course names, family names and outlines are shown in English. Lessons use English when a published translation is unavailable; the lesson shows a notice when this happens.
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Level 1Units: 4
Level 1 · Unit 1
The 260-day count
Meet the tonalpohualli, the Mexica count of days: 13 numbers and 20 day-signs making 260 days, read by the tonalpouhque.
- The count of days
- 13 × 20 = 260
- Day-signs 1 to 10
- Day-signs 11 to 20
- Checkpoint: the 260-day count
Level 1 · Unit 2
Trecenas, the year and the codices
Explore the 13-day trecenas, the 365-day year, the 52-year binding of the years, the codices and the history of Tenochtitlan.
- Trecenas
- The 365-day year
- Year bearers and the New Fire
- Codices and Tenochtitlan
- Checkpoint: trecenas, years and codices
Level 1 · Unit 3
Counting the days
Practise the 260-day count: name any day by its place, jump 13 or 20 days, list all 20 trecenas and find the trecena of any day.
- Find any day of the count
- Jumps of 13 and 20 days
- The twenty trecenas
- Which trecena is it?
- Checkpoint: counting the days
Level 1 · Unit 4
Glyphs, names and directions
How days were written with dots and glyphs, base-20 counting, Nahuatl numbers and calendar names, signs and the four directions, and the Lords of the Night.
- Writing a day
- Calendar names
- Signs and the four directions
- The Lords of the Night
- Checkpoint: glyphs, names and directions
Level 2Units: 4
Level 2 · Unit 1
The Xiuhpohualli
The veintena festivals, debates about when the year began, naming the years with the four year bearers, and the 52-year bundle.
- Festivals of the veintenas
- When did the year begin?
- Naming the years
- The 52-year bundle
- Checkpoint: the Xiuhpohualli
Level 2 · Unit 2
New Fire and Nahua traditions today
The Toxiuhmolpilia New Fire ceremony, Huixachtlan and 1507, Nahua communities today, and living day-count traditions approached with respect.
- Toxiuhmolpilia: the New Fire
- Huixachtlan, 1507 and the sources
- Nahua communities today
- Living day-counts, with respect
- Checkpoint: New Fire and traditions today
Level 2 · Unit 3
Working with the Calendar Round
Why year names step as they do, turning European years into Tenochtitlan year names, finding a year's place in the 52, and Calendar Round dates.
- How the counts mesh
- From European year to year name
- Finding a year in the cycle
- Calendar Round dates
- Checkpoint: the Calendar Round
Level 2 · Unit 4
Reading the Sun Stone
The Sun Stone's history, the story of the Five Suns, what its rings show and what scholars debate, and common myths about the "Aztec calendar".
- The stone in history
- The Five Suns
- Reading the rings
- What the stone is not
- Checkpoint: the Sun Stone