Muhammad had died on June 8, 632, and Khalid now owed his high military command to Muhammad’s earthly successor (khalifa or caliph) and leader of the believers (amir al-mu’minin), a slight, elderly former merchant with sunken cheeks and a thin, dyed beard, named Abu Bakr.2 In promoting Khalid, the caliph had acknowledged the general’s loyal service during the previous decade.
