sentences:  After the latter died in 867 his brother 'Ubaydallah had taken over the offices.In opposition to Ubaydallah, Muhammad sent another uncle, Sulayman ibn 'Abdallah, as his representative in Iraq, and Sulayman was able to gain the posts at the expense of Ubaydallah, although the latter would eventually recover them.The weakness of Muhammad's rule in Khurasan would eventually lead to the end of Tahirid rule there.