Gens: SEIUS  
Created: 28th October 2014
Update:  28th October 2014
Status Republic: Patrician:     Pleb. Nobilis:       Senatorial:      Eques Romanus: X
Republican Family / Cognomen
Patrician n/a
Pleb. Nobilis n/a
Senatorial n/a
Equestrian none, Postumus
Imperial Family / Cognomen
Imperators n/a
Consular Fuscianus, Seneca, Superstes, Tubero, Veranus
Senatorial none, Carus, Quadratus Sillianus
Equestrian none, Avitus, Maximus, Quadratus, Strabo
Republican Consuls, Tribunes with consular power, Dictators, Magister Equitum, Censors 0
Imperial Consuls and Emperors 5 excl. S312
Notes: Still no satisfactory explanation for L.Seius Tubero's (cos suff 18) cognomen, since Strabo was not married to a Iunia Tubero. 
That Seius Strabo adopted an Aelius Tubero seems unlikely, but possible.
Articles Adams, Freeman: "The Consular Brothers of Sejanus", in The American Journal of Philology , vol.76, 1955, pp.70-76, with stemma p.75
Corbier, Mireille: "La famille de Séjan à Volsinii ; la dédicace des Seii curatores aquae", in Mélanges de l'Ecole française de Rome. Antiquité T. 95, 1983. pp.719-756
discusses the new inscription with A. and L. Seius, curatores aquae.
Sumner, G.V.: "The Family Connections of L. Aelius Seianus", in Phoenix, Vol. 19, 1965, pp.134-145 with stemma p.137. 
He does not accept that Cosconia was married to Seius Strabo.
Syme: Augustan Aristocracy (P1986), chapter XXII Kinsmen of Seianus pp.300-312 with stemma at back. He argues that Seius Tubero was the son
 of Strabo's 1st wife Iunia by an earlier marriage to an Aelius Tubero, and that Strabo adopted his stepson who became Seius Tubero.
Changes
RE3
M.Seius L.f.
eques
ad cur 74
?
 
RE4   RE12
M.Seius Q.Seius Postumus
eques Romanus ab Ostia eques Romanus
ment 52-46 † 46 † 58 poisoned by Clodius
Caesarian 
trib Aem.
?
 
REPUBLIC  
IMPERIAL                                                    
 
M.Seius A.Seius
eques
~ Terentia A.f., sister of 
A.Terentius Varro Licinius Murena cos 23 BC
   
A179 RE59 S322 RE15 S313 RE2  
L.Aelius Gallus L.Seius Strabo   L.Seius A.Seius L.Seius
praef Aegypti ab Volsinii, Etruria, eques Romanus IIvir Panormus related to Seius Strabo ?
c.26-24 BC praef praet 14AD, praef Aegypt 15-16 † 16 procos Sicilia 27/23 BC curatores aquae at Volsinii
1 ~ (Iunia), sister of Q.Iunius Blaesus ? = L.Seius L.f. Fir[mus?] trib Aem.
cos suff 10 AD
2 ~ Cosconia Galitta, sister of 
adopted Ser. Cornelius Lentulus Maluginensis cos 10 AD
   
A255 RE133 1   S324 RE17 S312 S319 RE13 CIL XI-7269
L.Aelius L.f. (Gallus?) Seianus       L.Seius Tubero   (Seius) Seius Quadratus L.Se[…]
* 20/16 BC cos 31 † cos suff 18 cos an inc not a senator aedil or q at Volsinii 37
praef praet 14-31 leg of Germanicus 16 uncertain if involved in Seianus' fall 32
sacerdos (pont?) 31 in Germ Inf he exists
~ Apicita accused 24
 
A267 RE57   C412 A297 RE174b/d FOS14 S325 RE18
(L.) (Aelius) Gallus? Strabo   Dec. Capito Aelianus     (Aelia) Iunilla   M.Seius Varanus (or Veranus)
sacerdos in 31 †31 exc. †31 exc. cos suff 41
†31 exc. perhaps adopted by 20 engaged to Drusus
(not Gallus) C.Ateius Capito cos suff 5 son of CLAUDIUS
S314 RE6
L.Seius L.f. Avitus
trib Trom., praef alae 105
procur Aug Maur Ting 114/117
procur Aug Maur Caes 119
S321
D.Seius D.f. Seneca
trib Qui.
cos suff c.151/152
leg Aug Syria Palest 157
S317 RE9
P.? Seius Fuscianus
cos suff 161/169 cos ord 188
PUR
 
  S323 RE16 S81 M27 S329 FOS692 ? CIL VIII-7000 +19418
Seius Seius Superstes Sallustius (Macri[ni]nus ?) Seia Maxima   M.Seius Cn.f. Maximus
cos suff a 193 uncertain identity eques ab Cirta, trib Quir.
curat operum locorumque publicorum 193 ~ Sex.Anicius magistracies at Cirta
Saturninus sub Caracalla
    ab Uzappa
   
S316 RE8 S327 RE20 S101 RE22 S330 RE24 FOS693
Seius Carus   Seia Fuscinilla Cneia Seia Herennia Sallustia Orba Barbia Orbiana Seia Potitia Consortiana
† 219 exc. AUGUSTA clar fem sub Severans
senator patron of Thibaris in Africa
grdson of Fuscianus 225/6 ~ Imp M. AURELIUS SEVERUS ALEXANDER
imp 222-235  
S328 RE21 R98  
Seia M.f. Gaetula Roscius Potitus Memmianus
c.230/250 clar vir
~ M.Naevius Censitus
↓
UNKNOWN YEAR                                                            
S326 S315 RE7
A. Seius Zosimianus C.Seius M.f.Calpurnius Quadratus Sillianus (not Sittianus)
eques Romanus trib Quir., IIIvir capitalis, q Africa, tr pl,
praef coh, tr leg XI Claud pr pereg, procos Narbo
decurion Antias ab Cirta?