Abu Ubaidah ibn al-Jarrah
On his deathbed, Omar vacillated on his succession. However, it has been reported that he said that if Abu Ubaidah ibn al-Jarrah, Khalid ibn Walid or Salim, the mawla and freed Persian slave, were alive he would have appointed one of them his successor. Omar finally appointed a committee of six persons to choose a caliph from amongst them: Abdur Rahman bin Awf, Saad ibn Abi Waqqas, Talha ibn Ubaidullah, Uthman ibn Affan, Ali ibn Abi Talib and Zubayr ibn al-Awwam.