Saudi Arabia on Friday began expelling more than a thousand Nigerian women on a religious pilgrimage because they had arrived without male guardians, the first time it sent back such a large group in enforcement of strict rules governing women. The ministry that oversees the pilgrimage, or hajj, said the 1,100 women had violated a longstanding law by traveling without an immediate male relative, adding that women of all nationalities under the age of 45 must have a male guardian during the hajj. The women, who arrived in Jidda in three groups, were detained after landing at the international airport starting Monday. Nigeria’s pilgrimage commission said a bilateral agreement exempted its citizens from the rule.