Mentuhotep II
Even though the Age of the Pharaohs is recognized for its length, it almost came to an end much sooner without Mentuhotep II. For this reason, even though his name may not be well-known to many people, he belongs on this list.
Around 2200 BC, the Sixth Dynasty came to an end, along with what is known as the Old Kingdom of Egypt. It was followed by the First Intermediate Period, a 125-year period marked by conflict and anarchy. The pharaohs of Upper Egypt governed from Thebes during this time, while those of Lower Egypt created a new capital at Heracleopolis. Egypt was no longer a one entity during this time. At least four and a half dynasties are supposedly included in the First Intermediate Period, but we know little little about their kings. Many of them had brief reigns that lasted only a few years, and today all we know of them is as names on a list of monarchs.
As the sixth pharaoh of the 11th Dynasty, Mentuhotep II controlled Upper Egypt alongside the 10th Dynasty, which ruled over Lower Egypt. He began a military campaign against Lower Egypt in the 14th year of his rule, and he gradually but steadily drove the opposing forces further north. Around this time, Merikare, the rival pharaoh of the 10th Dynasty, passed away, facilitating Mentuhotep's advancement and ultimately leading to the unification of the two Egypts with the conquest of Heracleopolis. Mentuhotep II established the Middle Kingdom, Egypt's next golden age, and has been referred to be the "second founder" of Egypt in later inscriptions.
Reign: 2060–2009 BC (11th Dynasty)
Predecessor: Intef III
Successor: Mentuhotep III