Original: They are also part of the chain of holders of the office of Caliph , as recognized by most Muslims , the only period in which the Shia Imamate and the Caliphate were united to any degree , excepting the Caliphate of Ali himself .
Simplified: They are also part of the chain of holders of the office of Caliph , as recognized by most Muslims , the only period in which the Shia Imamate and the Caliphate were united to any degree .