Horus Qa’a is the last king of the 1st Dynasty. His relationship with his predecessors or successors is unknown. The fact that he built his tomb next to Semerkhet’s and Den’s could be seen as an indication that he was closely related to both kings.
Only the first 2 years of Qa’a’s reign have been preserved on the Cairo Fragment CF1 of the Annals Stone. Manetho, credits him with 26 year, while the Turin King-List records the unlikely high number of 63 years.
A fragment of a bowl found at Saqqara mentions Horus Qa’a’s second Heb-Sed which, if the festival was celebrated the first time during his 30th and the second time during his 33rd year in power, would indicate a reign of at least 33 years. The large number of mastabas at Saqqara dated to his reign also points at a long reign, as well as the findings that his tomb was built in several stages interrupted by fairly long periods.
Several cultic activities are recorded on year labels, most the usual types of cults, others the foundation of a religious building named qA.w-nTr.w.
Seal impressions and other sources attest Qa’a’s name at Saqqara, Abusir and Abydos, while a rock inscription found near Elkab in the south of Egypt may perhaps point to a mining expedition in Egypt’s Eastern Dessert.
An ivory gaming rod and vessels of Syro-Palestinian origin found in the Saqqara tombs dated to his reign, suggest at least trade with this region. A carving on the gaming rod showing the king as victorious over an Asiatic person may either refer to an actual military campaign or it may be symbolic.
With Horus Qa’a, the 1st Dynasty comes to an end. While the king-lists do not tend to distinguish between this and the 2nd Dynasty, and list the kings of both dynasties in the same sequence, the first kings of the 2nd Dynasty would favour Saqqara for their burials rather than Umm el-Qa’ab.
With Qa’a, the gruesome practice of retainer sacrifice also came to an end. These two, and perhaps other factors may have made Manetho decide to end the 1st Dynasty with Qa’a.
Two ephemeral Horus Names, one of “Ba” attested once and the other of Seneferka attested twice, point at a short period of upheaval following Qa’a’s reign. The name of the first king of the 2nd Dynasty, Hotepsekhemwi, meaning “the two powers are at peace” may hint at a brief period of division that ended with Hotepsekhemwi’s reign.
The name of Hotepsekhemwi was also found at Qa’a’s tomb at Umm el-Qa’ab, which suggests that Qa’a was buried or reburied by Hotepsekhemwi, or that the latter may have seen cultic activity at Qa’a’s tomb as a way to legitimise his own reign.