Will of Khalifa Abubeker Ebn Abu Kohafa (appointing Umar as his successor)

In the name of the most merciful Allah,

This is the testament of Abubeker Ebn Abu Kohafa, which he made at that time when he was just going out of this world, and entering into the other; a time in which the infidel shall believe, and the wicked person shall be assured, and the liar shall speak truth.

I appoint Omar Ebn Al Khattab my successor over you; therefore hearken to him, and obey him. If he does that which is right and just, it is what I think and know of him. If he does otherwise, every man must be rewarded according to his works. I intend to do for the best, but I do not know hidden things; but those who do evil shall find the consequences of it. Fare ye well, and the mercy and blessing of Allah be upon you.

Empire under Omar Ebn Al Khattab (637 CE)

Mecca (Arabia)
Medina (Arabia)
Basra (Iraq)
Kufa (Iraq)
Jazira, in the upper reaches of the Tigris and Euphrates
Syria
Iliyā’ (Palestine)
Ramlah (Palestine)
Upper Egypt
Lower Egypt
Khorasan (Persia)
Azerbaijan (Persia)
Fars (Persia)

“Yet the abstinence and humility of Umar were not inferior to the virtues of Abubeker; his food consisted of barley bread or dates; his drink was water; he preached in a gown that was torn or tattered in twelve places; and a Persian satrap who paid his homage to the conqueror, found him asleep among the beggars on the steps of the mosque of Medina.” [The Decline and Fall of the Roman Empire, Gibbon]