More on the 12th dynasty.

Source:
[link to www.crystalinks.com]

Some interesting extracts:

"The kings of the 12th Dynasty ruled the country firmly and were able to maintain the power of balance between the central authorities and the local administrations, to their own advantage. They also imposed their rule on northern Nubia and pacified the Bedouins in the deserts to the east and west of the Nile Valley. Imposing fortresses were built in Nubia and at the Eastern border, to protect trading routes from raiding Bedouins."
.........
"In Nubia, Amenemhet I first pushed his army southward to Elephantine, where he consolidated his rule and seems to have been satisfied for a number of years. This expedition was apparently lead by Khnemhotpe I, governor of the Oryx nome, who traveled up the Nile with 20 boats. But by year 29 of his rule, the king appears to have no longer been happy with the lose trading and quarrying network with Nubia that we find in the Old Kingdom.

The new policy was one of conquest and colonization with the principle aim of obtaining raw materials, especially gold. An inscription at the northern Nubian site of Korosko about half way between the first and second cataracts (rapids) states that the people of Wawat (northern Nubia) were defeated in his 29th year, and he apparently drove his army as far south as the second cataract."

In order to protect Egypt and fortify captured territory in Nubia, he founded a fortress at Semna and Quban in the region of the second Nile Cataract, which would begin a string of future 12th Dynasty fortresses. Along with protecting his newly acquired territory and the gold mines in Wadi Allaqi, he also created a stranglehold over economic contacts with Upper Nubia and further south. We also know that he constructed a fortress at Mendes named Rawaty."
........
Senusret I
He continued his father's aggressive expansionist policies against Nubia by initiating two expeditions into this region in his 10th and 18th Years and established Egypt's formal southern border near the second cataract where he placed a garrison and a victory stele. He also organized an expedition to a Western Desert oasis in the Libyan desert. Senusret I established diplomatic relations with some rulers of towns in Syria and Canaan.

etc. etc.