The getRuler1 arguments are appended to the api call as such:
&getRuler1={ruler name}
The possible arguments are:
ADDEDOMAROS
Aedic Sia
AESV
AGR
ALE SCA
Amminus
ANDOCO
ANTED (Dobunni)
ANTED (Iceni)
ANTEDIO SIA
AVN CO
BODVOC
CAM CVN AGR
CAN DVRO
CARA[TACUS]
Cat
CATTI
Commios
COMVX
CORIO
CRAB
Cunobelin
DIAS
DIRAS
Dubnovellaunos
DVMNOCO TIGIR SENO
ECE
ECEN
Ecen/Ece
ED(N)
Edn/Ed
EISV
Epaticcus
Eppillus
Gallo-Belgic
IATISON
IISVPRASV
INAM
Inam’/'Inara
Uninscribed
Potin
RVES
SAENV
SAM
SEGO
SVB ESVPRASTO ESICO FECIT
Tasciovanus
Tincomarus
Vep
VEP CORF
VEPO CORF
Verica
VOLISIOS CARTIVEL
VOLISIOS DUMNOCOVEROS
VOLISIOS DUMNOVELLAUNOS
Vosenos
If a space is present in the name replace this with %20 to complete the string. Not ideal I know!