After the conquest of Egypt, Amr b Al 'Aas became the first Governor of Egypt. Egypt was the richest province in the Muslim dominions, but the revenues that 'Amr b Al 'Aas sent to Madina from Egypt were not commensurate to the importance of the province Amr b Al ~Aas was a good administrator and a skilful General, but he was not an expert in financial affairs. There were complaints that the financial affairs of the province were not managed efficiently.
Later, Umar partitioned Egypt into two provinces, namely Upper Egypt with the capital at Fayyum, and Lower Egypt with the capital at Fustat. 'Amr b Al 'Aas remained the Governor of Lower Egypt, while Abdullah b Sa'ad b Abi Sarah was appointed as the Governor of Upper Egypt.
The measure of the partition was not popular with the people. 'Amr b Al 'Aas felt dissatisfied that his charge had been curtailed. Umar was a stern and hard task master and he suppressed all opposition with a stern hand.
"When a person dies, his works end, except for three: ongoing charity, knowledge that is benefited from, and a righteous child who prays for him."
Prophet Mohammed (PBUH)
"The best of what a man leaves behind are three: a righteous child who supplicates for him, ongoing charity the reward of which reaches him, and knowledge that is acted upon after him."
Sunan Ibn Mājah
"Every day two angels come down from Heaven and one of them says, 'O Allah! Compensate every person who spends in Your Cause,' and the other (angel) says, 'O Allah! Destroy every miser.'"
Sahih Bukhari