7 ) ▁was ▁a ▁Mexican ▁Qu aker ▁leader , ▁peace ▁activ ist , ▁language ▁interpreter ▁and ▁diplom at . ▁ ▁Born ▁in ▁Mate h ual a , ▁San ▁Luis ▁Pot os í , ▁Mexico , ▁Sein ▁was ▁a ▁founder ▁of ▁the ▁Mexico ▁City ▁Fri ends ▁Me eting ▁and ▁Fri ends ▁House . ▁He ▁was ▁married ▁to ▁a ▁Swiss - born ▁Qu aker , ▁Su z anne ▁Sein . ▁He ▁was ▁an ▁interpreter ▁at ▁the ▁found ing ▁of ▁the ▁League ▁of ▁Nations ▁and ▁later ▁with ▁the ▁International ▁Labor ▁Organ ization . ▁He ▁also ▁promoted ▁the ▁work cam ps ▁of ▁the ▁American ▁Fri ends ▁Service ▁Committee ▁in ▁Mexico . ▁He ▁was ▁part ▁of ▁the ▁larger ▁struggle ▁in ▁Latin ▁America ▁for ▁non - vi ol ent ▁social ▁change . ▁He ▁was ▁often ▁invited ▁to ▁speak ▁on ▁peace ▁in ▁the ▁United ▁States , ▁and ▁was ▁a ▁strong ▁yet ▁tact ful ▁voice ▁at ▁international ▁peace ▁con ferences ▁throughout ▁the ▁world . ▁The ▁Casa ▁He berto ▁Sein , ▁a ▁Qu aker ▁Center ▁in ▁Herm os illo , ▁Son ora , ▁Mexico ▁is ▁named ▁for ▁him . ▁ ▁References ▁ ▁External ▁links ▁ ▁Qu akers ▁in ▁Mexico ▁ ▁Category : 1 8 9 8 ▁birth s ▁Category : 1 9 7 7 ▁death s ▁Category : M ex ican ▁activ ists ▁Category : M ex ican ▁diplom ats ▁Category : M ex ican ▁Qu akers ▁Category : Pe ople ▁from ▁San ▁Luis ▁Pot os í <0x0A> </s> ▁In ▁queue ing ▁theory , ▁a ▁discipline ▁within ▁the ▁mathematical ▁theory ▁of ▁probability