Which civilization did not have a written language?

It's tricky to say definitively which civilization *did not* have a written language, as the archaeological record is always evolving. However, some civilizations are generally considered to have been pre-literate or to have had only rudimentary systems of writing, such as:

* The Indus Valley Civilization (Harappan Civilization): Their writing system, found on seals and other artifacts, is still undeciphered, making it difficult to determine the extent of their literacy.

* The Olmec Civilization: While they had a complex society, no deciphered writing system has been found.

* The Minoan Civilization: Their writing system, known as Linear A, is undeciphered, and they may have used it primarily for record-keeping rather than literature.

It's important to note that:

* "Civilization" is a complex term: There are many different ways to define it, and it's not always clear-cut. Some civilizations might have had complex social structures, impressive architecture, and sophisticated technology without a written language.

* Our knowledge is incomplete: Archaeological discoveries are constantly being made, and new evidence could shed light on previously unknown writing systems.

Therefore, it's safest to say that we cannot definitively say which civilization did not have a written language, as our understanding is constantly evolving.