Nitocris is not attested by any contemporary source: no decrees, no building projects and not even a mention in some highly placed official's biography. She is, however, mentioned in the Turin King-list, by the Greek traveller Herodotos and by Manetho, which may indeed confirm her existence.

According to Manetho, Nitocris constructed the "third pyramid". It is generally assumed that he meant the third pyramid of Giza, which has been built by Mykerinos. He may have confounded the name of Mykerinos (Men-kaw-re) with Nitocris' probable prenomen, Men-ka-re, which is mentioned in some of the king-lists.

Still according to Manetho, Nitocris has come to power when her brother was murdered. She took it upon herself to have her brother's murderers punished.

- History -