EQUESTRIAN PREFECTURES		30BC-	14-	37-	41-	54-	69-	81-	96-	117-	138-	161-	180-	192-	211-	250-
Title	Office	14AD	37	41	54	68	81	96	117	138	161	180	192	211	249	284	Notes and Area of Responsibility
praefectus	Aegypti	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	governor of Egypt (30 BC), ranked 1st until Vespasian
praefectus	praetorio	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	commander of the praetorian guard (2 BC)
praefectus	annonae	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	in charge of the delivery of food for distribution in Rome (7/14 AD)
praefectus	vigiles	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	commander of the 7 cohorts of the fire brigade / night watch (6 AD)
praefectus	legionis Aegypti	3	2	2	2	2	2	2	2	1	1	1	1	1	1	1	commanders of the legions in Egypt
praefectus	provinciae Mesopotamiae	0	0	0	0	0	0	0	0	0	0	0	0	1	0	1	governor of Mesopotamia (195 to 212/213 and from 240)
praefectus	provinciae Mesopotamiae	0	0	0	0	0	0	0	0	0	0	0	0	0	1	0	governor of Mesopotamia and Osrhoene (from 212/213 to 240)
praefectus	legionis Mesopotamiae	0	0	0	0	0	0	0	0	0	0	0	0	2	2	2	commanders of legions in Mesopotamia
Total		8	7	7	7	7	7	7	7	6	6	6	6	9	9	9
Note 1	For short periods there was only one praefectus praetorio, e.g. Aelius Seianus 16-31, Naevius Sertorius Macro 31-38, Sex.Afranius Burrus 51-62, M.Bassaeus Rufus 172-177.
Note 2	Mesopotamia was governed by a salary trecenarius (CCC) from 195. From 212/213-240 the province included Osrhoene.
Note 3	Gallienus (Imperator 253-268) transferred the commands of all legions from a senator (legatus legionis) to an eques, who received the title praefectus legionis.