Assertion: caliph | /r/CapableOf | rival that of the sunnis
Facets:
value: at one time
type: TEMPORAL
Source sentences:
text: Umayyad (661-750), Abbasid (750-1517) and then the Shi'a became a minority with their own leaders and successors, but at one time their caliphs rivaled that of the Sunnis.