A prudent President is well advised to convoke ad hoc Councils of State on issues of war and peace.
From the theatlantic.com
They have the power to convoke others.
From the time.com
Lambert, the Cardinal of Ostia was dispatched to convoke a synod at Worms, which began on September 8, 1122.
From the en.wikipedia.org
Messori explained that if a Pope decided he was no longer capable of leading the church, he would convoke a Consistory of all the world's Cardinals at the Vatican.
From the time.com
Only when a measure of peace-or at least stalemate-eased the power struggle between the army, old party cadres and Maoist radicals, did Chairman Mao decide to convoke the meeting.
From the time.com
In an emergency the Cabinet can convoke the Diet for an extraordinary session, and an extraordinary session may be requested by one quarter of the members of either house.
From the en.wikipedia.org
Also, as holder of the tribune's power, the emperor would convoke the Council of the People, lay legislation before it, and served as the council's president.
From the en.wikipedia.org
The praefectus urbi no long held the power to convoke the Senate, or the right of speaking in it, and was appointed by the Consuls instead of being elected.
From the en.wikipedia.org
However, the Governor is empowered to convoke the Legislature at or adjourn it to another place, when, in his opinion, the public safety or welfare, or the safety or health of the members require it.
From the en.wikipedia.org
More examples
Call together; "The students were convened in the auditorium"
A Convocation (Latin 'calling together', translating the Greek ecclesia) is a group of people formally assembled for a special purpose.
To convene, to cause to assemble for a meeting
A keyword ability that reduces how much mana you need to spend to cast a spell. See rule 702.48, "Convoke."