Emperors, Frontiers, and Foreign Relations 169OutsideRome,weseeforinstanceOtho’sadvisersdebatingtheprospects
ofthecivilwarof69:fivepersonsgivetheiropinions,includinghisbrother
andhispraetorianprefect,andtheprimeroleisplayedbySuetoniusPaulinus,
on the basis of his established reputation as a military man.^43 The advisers
whomMarcusAureliuswouldconsultonbothmilitaryandcivilmatters^44
werewithhimandCommoduswhenhedied(atSirmiumorVindobona)
in 180. Both Dio and Herodian report that it was against theiradvice that
theyoungCommodusmadepeace,abandonedtheMarcomannicwar,and
returnedtoRome.^45 Thisisacardinalinstanceoftheessentialweaknessof
thepositionoftheamiciorcomites.Itlaysolelywiththeemperorwhetherto
havethemwithhim,toconsultthemonanyparticularissue,ortotaketheir
advice.Theyhadnopowerbase,werenobody’sdelegatesorrepresentatives,
andcouldnotcompelhimeveniftheywereunanimous.
Theotheressentialfeatureoftheinstitutionoftheconsiliumintheearly
Empirewastheabsenceofanydistinctionoffunction(juridical,administra-
tive,political,ormilitary)betweenitsmembers.Inthisrespectthestructural
developmentsofthethirdandfourthcenturiesbroughtsomechanges,not
easilydefined.Inthecenturyfrom250to350thefewbriefaccountswehave
ofdiscussionsbetweentheemperorandadviserstendtosingleoutpersons
holding specific military ranks,praefecti,tribuni,orduces;^46 we have no evi-
dencetoindicatewhetherthemagistri militumcreatedbyConstantinebegan
atoncetoactasmilitaryadviserstotheemperor.WhenAmmianus’narra-
tiveisavailable,fortheyearsfrom353onwards,wehavevariousdescriptions
ofcouncilsofwar:beforeCtesiphonin363;whenValentinianwashesitating
in 364 between repelling the Alamannic invasion of Gaul and confronting
thestillvaguelyreportedcoupof ProcopiusintheEast;andlaterwhenhe
wasdissuadedbyhisadvisersfrommarchingfromRhinetoDanubeagainst
theQuadiuntilhehadmadepeacewiththeAlamanniandhadwaitedfor
thespringof375.^47 Butunfortunatelyonlytheaccountofthecouncilofwar
heldbyValensbeforeHadrianoplein378givesanyindicationoftheranks
orofficesofthepersonsconsulted:thepersonsof‘‘variousranks’’(potestates
variae)includedSebastianus,themagister peditum(themasteroftheinfantry)
whowasinfavourofimmediateaction,andVictor,themagisterequitum(the
- Tacitus,Hist.2,31–33.
44.HA,v. M. Ant.22.3. - Dio73,1,2;HerodianI,6.Forthetreatynegotiations,seetextton.101.
46.ERW,125–22. - Ammianus24,7,1;26,5,8–13;30,3;(seefurtherbelow).NotealsoEunapius,Fr.
42 (FGHIV, pp. 31–33) on the discussion of the Goths’ request to be allowed across the
Danube.