A judicial commission consisting of Justice Munir and Justice Kayani of the Pakistan Supreme Court, constituted in 1954 to ascertain if Ahmediyas were Muslims, could not give a ruling as no two ulema could agree on the precise definition of a Muslim.
Islam had ceased to be a monolith immediately after the death of Prophet Mohammed. The schism originated on the issue of inheriting the Prophet's temporal and spiritual legacy.
Shias believe that Hazrat Ali, the prophet's nephew and son-in-law, was the rightful heir and that the prophet, during his lifetime, had given adequate indications of this.
As such, the Shias do not recognise the first three caliphs (religious rulers regarded as the successors of the Prophet) and consider them usurpers.