"Umar had become the second of the ‘Rightly Guided’ (Rashidun) caliphs in 634, when Abu Bakr died. Around fifty-three years old, he was famous for his physical strength, stubbornness, and literacy. Although he did not lead Muslim armies in person, he was an outstandingly competent commander-in-chief, able to dictate military strategy hundreds of miles from Medina, trusting his generals to find the most effective means to achieve the wider goals of the expanding Islamic state. As caliph he carefully curated his public image: on entering Jerusalem to take possession of the city from the patriarch Sophronius, he appeared in ragged clothes, dirty from his long journey, so that his humble appearance would contrast pointedly with the churchman’s finery."