The church council that I had was Constantinople III. The person that convened the council was Emperor Constantine IV. The council lasted for last then a year. it lasted from November 7th, 680 A.D. to September 16th, 681 A.D. The place where the council met was an imperial palace in a large domed hall called Trullo.
Emperor Constantine IV and only 43 bishops attended the first few sessions. That made this the smallest church council. More people attended the later sessions. The council had around 174 members at the end. For about 11 sessions the emperor came and then for the last sessions, he did not come. The council had around 18 sessions. The topics they discussed the human and divine wills of Jesus. The council did not produce any canons or doctrines as far as I know. I could not find a lot of information.
Emperor Constantine IV and some bishops.