Merenre I was the oldest surviving son of Pepi I and Ankhenespepi II. He may perhaps have married his aunt Ankhenespepi I, and widow of Pepi I and may have been the father rather than the brother of his successor Pepi II. For children attributed to him were Iput II (although she may also have been a daughter of Pepi I), Neith and Ankhenespepi III, all three later wives of Pepi II.
The 40 years credited to him by the Turin King-list is probably due to a bad restoration or interpretation of the papyrus. There may have been a confusion between his prenomen, Merenre, and that of his father, which was Merire. It is now generally believed that Merenre I’s reign was short, some 7 to 11 years.
In his 5th regnal year, Merenre I travelled to the 1st cataract in the South of Egypt, to receive tribute from the Nubian chiefs. The governor of Elephantine led several military campaigns into Nubia during his reign.
His name has also been found in the Wadi Hammamat and in the alabaster quarries of Hatnub, indicating a continued mining activity in these two regions.
His pyramid, in Saqqara South, appears not to have been completed. The mummy found inside the pyramid would be the oldest known complete royal mummy, if it actually is Merenre I’s.