Contemporaneous sources

South Saqqara Stone

In addition to the above attestations contemporaneous with Userkare's reign, details about his time on the throne were once given on the nearly contemporaneous South Saqqara Stone, a royal annal of the Sixth Dynasty dating to the reign of Merenre Nemtyemsaf I or Pepi II. It was uncovered by Gustave Jéquier in a storeroom of the mortuary temple of Iput II, northwest of the pyramid complex of Pepi II. The stone had been reused as lid for the sarcophagus of queen Ankhesenpepi III, though this lid did not originally belong with the sarcophagus.

An estimated 92% of the original text was lost when the stone was roughly polished, possibly in the late first intermediate to early Middle Kingdom period (c. 2050 – 1650 BC). The presence of Userkare on the annal can nonetheless be inferred from a large space between the sections concerning the reigns of Teti and Pepi I as well as from traces of a royal titulary in this space. Although the text reporting Userkare's activities is lost, its length suggests that Userkare ruled Egypt from two to four years, with the former seen as less probable than the latter.

Historical sources

Several ancient sources mention Userkare. The first is the Abydos king list, a list of kings written during the reign of Seti I (c. 1290 – 1279 BC), over 1,000 years after the early Sixth Dynasty. Userkare's cartouche occupies the 35th entry of the list, between those of Teti and Pepi I, making him the second pharaoh of the dynasty.

Userkare was possibly also listed on the Turin canon, a king list composed during the reign of Ramesses II (1279 – 1213 BC). Unfortunately, a lacuna affects parts of the second line of the fourth column of the papyrus on which the list was written, the location were Userkare's name might have been located. If Userkare was indeed mentioned as Pepi I predecessor, then what remains of his entry on the papyrus indicates that he was credited with 20 years of reign. This is now widely considered untenable because of evidence from the South Saqqara stone.

As a legitimate ruler

The Egyptologists William Stevenson Smith, William C. Hayes and Nicolas Grimal believe that Userkare briefly ruled Egypt either as a legitimate stopgap ruler or as a regent with queen Iput I. Indeed, Teti's son Pepi I reigned for c. 50 years, indicating that he was probably very young at the death of his father, too young to immediately assume the throne. The theory that Userkare was merely a regent is rejected by Naguib Kanawati, on the basis that Userkare seems to have been mentioned on the Turin canon which otherwise lists only kings, is present in the Abydos king list and holds full royal titulary, something reserved exclusively to reigning pharaohs. In support of the hypothesis that Userkare was a legitimate stopgap ruler, Grimal stresses that he is well attested by historical and contemporaneous sources, in particular the South Saqqara Stone. This seems in contradiction with the idea that, being illegitimate, he was victim of a damnatio memoriae by his successor Pepi, whereby Pepi would have attempted to erase all memory of Userkare from official records. In addition, there is no direct evidence of difficulties associated with Pepi I's rise on throne in the archaeological record, which one could expect had Userkare been a usurper. Rainer Stadelmann and Michel Baud stress that there is no clear evidence for a damnatio memoriae targeting Userkare. For example his funerary complex may have been planned yet never erected, which they find would provide a better explanation for its absence than a "speculative" attempt on Pepi I's behalf to erase traces of his predecessor's rule. Alternatively Userkare may have been legitimate yet only reigned jointly with Pepi I in a true coregency, although as the Egyptologist Christoffer Theis points out this hypothesis lack direct evidence.

Vivianne Gae Callender—who thinks that Userkare was the target of some kind of damnatio memoriae—has put forth another theory in which Userkare was a legitimate son of Teti born while his father was king, but not his first-born son. In this hypothesis, Userkare's claim to the throne would rely on his being born after Teti had assumed power, while Pepi I would be the eldest son of Teti yet born before Teti's elevation to power. In particular Teti's eight to 12 years of reign would imply that Userkare would have been around 10 at the time of his coronation and facing a resentful older brother, possibly explaining the paucity of attestations of his rule. Morris Bierbrier goes even further by suggesting that the "ambitious" future pharaoh Pepi I might have had Userkare killed. Although not going as far, Karola Zibelius-Chen too thinks that Userkare was a legitimate son of Teti facing his half brother's opposition. She points in particular to the existence of two distinct queens of Teti bearing the title of "King's mother". One is Pepi's mother Iput while the identity of the second one is uncertain. For Zibelius-Chen and Callender she could well be the queen who later conspired against Pepi and was prosecuted when the conspiracy was discovered.

As a usurper to the throne

The Egyptian priest Manetho wrote a history of Egypt, the Aegyptiaca, in the 3rd century BC during the reign of Ptolemy II (283 – 246 BC). No copies of the Aegyptiaca have survived, and it is now known only through later writings by Sextus Julius Africanus (c. 160 – 240) and Eusebius (c. 260/265 – 339). According to the Byzantine scholar George Syncellus (fl. 800), Africanus's version of the Aegyptiaca reported that Othoês—the hellenized name of Teti—was murdered by his bodyguards or attendants. No other ancient source or archaeological evidence has come to light directly confirming this story. Based on the Aegyptiaca Egyptologists have found it plausible that Userkare participated in or at least benefited from Teti's assassination, despite Userkare's own absence from the Aegyptiaca. Userkare's name is theophoric and incorporates the name of the sun god Ra, a naming fashion common during the preceding Fifth Dynasty. Against this opinion, Theis observes that other kings of the Sixth Dynasty, Merenre and Pepi II—whose throne name was Neferkare—did include Ra in their names as well. Since Teti was not a son of the last Fifth Dynasty king Unas, some Egyptologists have proposed that Userkare could have been a descendant of a lateral branch of the Fifth Dynasty royal family who briefly seized power in a coup, and may even have reigned only over a small part of Egypt. In possible support of this theory is the discovery of stone blocks inscribed with Teti's mother Seshseshet's name reused as building material in the core of Pepi's pyramid. The reliefs of the blocks had been deliberately damaged and Verner proposed that Userkare may be responsible for this.