The Great Pyramids of Giza were built around the year 2,500 BCE, during the Old Kingdom period of Egyptian history. The pyramids were burial tombs for powerful Pharaohs like Khufu.

Contrary to popular belief, the Ancient Egyptians only constructed pyramids for a relatively brief time in their civilization’s lengthy history. In fact, the majority of the pyramids were built during the Old Kingdom, with a few other remnants being erected in the Middle Kingdom. By the time of the New Kingdom, pyramids had fallen entirely out of use; by then, most pharaohs favored rock-cut tombs instead. We cannot be entirely sure why Ancient Egypt’s preference for pyramids died out, but this was most likely due to a combination of factors (which are seen across many complex societies), including architectural innovation, technological improvements, the evolution of styles, changing religious beliefs, and a fluctuation in the availability of money and physical resources.

By the Sixth Dynasty royal authority had begun to weaken as nobles acquired more political influence. The Niles extreme flooding, disastrous droughts and border threats have also been cited as factors in the decline of the Old Kingdom. Political and military overextension was not an issue during the Old Kingdom. 

The Old Kingdom, spanning from 2686 - 2181 BCE, was the period in which most of the pyramid-building occurred. This largely stemmed from the fact that civilized rule began in this period and the rulers first realized decided that rulers should be memorialized and buried in these large monuments. Pyramid-building tapered off towards the end of the Old Kingdom and beginning of the Middle Kingdom because rulers during this time realized how building the pyramids was incredibly time-consuming and expensive, not to mention that they were often robbed by tomb raiders.

The Fifth and Sixth dynasties were the last two dynasties of the Old Kingdom period of Egyptian history. During the rule of the Fifth Dynasty, the authority of the Pharaoh was slowly eroded by the growing power of the Egyptian nobility and priesthood. Egypt underwent a prolonged period of decline and destabilization which eventually led to the fall of the Old Kingdom and the beginning of the First Intermediate Period.

The Old Kingdom of ancient Egypt declined during the rule of the Fifth and Sixth Dynasties, finally dissolving in the 22nd century BCE. There were several factors that contributed to the decline of the Old Kingdom, but the most important issue was the erosion of the authority of the Pharaoh and the accompanying growing power of the nobility and priesthood. This led to the decentralization of power in Egypt and constant power struggles and civil war.

The Great Pyramids of Giza were most likely built during the reign of Khufu (in the fourth dynasty of the Old Kingdom). After Khufu’s reign, the Old Kingdom entered a gradual period of decline. Most of the pyramids built after Khufu’s death were much smaller and less expensive. Especially during the fifth and sixth dynasties.

The pyramids built during the middle years of the Old Kingdom (such as the Great Pyramids of Giza) were much larger than the pyramids that were built during the fifth and sixth dynasties (towards the latter years of the Old Kingdom). This is primarily the result of Egypt’s gradual economic decline and the subsequent inability of rulers to fund the construction of great monuments.