Marwan who was appointed as Govenor by Moawaiya. He used to curse on Imam Ali bin Abu Talib (according to Moawiya’s orders) in his khutba in the mosque, some people do not want to listen it and they used to leave the mosque after the prayer. So Marwan changed the way, Abu Saeed Khudari (rz) objected him but other people used to listen all.
Please keep in mind that Marwan is the same person whom holy Prophet expelled him out from Medina with his father. But when Uthman bin Affan became caliph, He brought father and his son in Medina again. Uthman married his daughter with Marwan, Marwan was the special secratory of the third caliph.(khilafat o Malookiyyat by Molana Moudoodi and other Sunni history books)