How do you conduct a census without a written language?

The Inca Census and the Quipu …

Back in the middle part of the last millennium, the Inca people of South America regularly conducted a census.

Maybe that’s not surprising as the Romans were known to conduct regular censuses as early as 435 BC.

But, what is remarkable is that the Incas had no written language.

So, how did they conduct a meaningful census without a written language?

They used a device called a Quipu.

A quipu is essentially a group of wool and cotton strings (or Llama hair) tied together. The strings are dyed in many different colors, and they are joined together in many different manners and they have a wide variety and number of knots tied in them.

Together the type of wool, the colors, the knots and the joins hold information that was once readable by several South American societies.

So a quipu communicated through color, texture, size, forms, and other characteristics that denoted some interaction with the reader.

The number 586 represented on a single quipu strand

Quipu Meanings

Quipus have not yet been deciphered, but some educated guesses about what they represent have been attempted.

A quipu usually consists of colored cotton cords with numeric values perhaps encoded by knots in the base_10 positional system.

Many uses that are known today for the quipu are: census counts, taxes, a count of items that should be bought or sold and basic numerical data.

The Incas used the quipu to maintain a record of economic output, and regularly ran a census that counted every one from infants to “old blind men over 80”.

When they arrived in 1532, the Spanish conquistadors viewed the quipu with great suspicion. Thousands of quipus were destroyed in the 16th century.

Today only about 600 Incan quipu survive.

The ability to decipher the quipu died along with last of the Incas….so their hidden information, and the Inca history, may never be fully discovered.

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