, ▁whose ▁wife ▁had ▁been ▁unable ▁to ▁conce ive ▁a ▁male ▁he ir . ▁From ▁ 1 6 8 0 ▁to ▁the ▁end ▁of ▁his ▁life , ▁Marco ▁d ' Av iano ▁became ▁a ▁close ▁conf id ant ▁and ▁advis er ▁to ▁him , ▁providing ▁the ▁ir resol ute ▁and ▁often ▁inde cis ive ▁em peror ▁with ▁guidance ▁and ▁advice ▁for ▁all ▁problems , ▁political , ▁economic , ▁military ▁or ▁spiritual . ▁His ▁force ful , ▁ener get ic ▁and ▁sometimes ▁passion ate ▁and ▁fier y ▁person ality ▁proved ▁a ▁good ▁complement ▁for ▁Leopold ' s ▁Ham let - like ▁t endency ▁to ▁allow ▁end less ▁doub ts ▁and ▁sc ru ples ▁to ▁par aly se ▁his ▁capacity ▁for ▁action . ▁As ▁the ▁danger ▁of ▁war ▁with ▁the ▁Ott oman ▁Tur ks ▁grew ▁near , ▁Marco ▁d ' Av iano ▁was ▁appointed ▁by ▁Pope ▁In noc ent ▁XI ▁as ▁his ▁personal ▁en voy ▁to ▁the ▁Emperor . ▁An ▁imp ass ioned ▁pre acher ▁and ▁a ▁skill ful ▁medi ator , ▁Marco ▁d ' Av iano ▁played ▁a ▁cru cial ▁role ▁in ▁resol ving ▁disput es , ▁rest oring ▁unity , ▁and ▁energ izing ▁the ▁arm ies ▁of ▁the ▁Holy ▁League , ▁which ▁included ▁Austria , ▁Poland , ▁Ven ice , ▁and ▁the ▁Pap al ▁States ▁under ▁the ▁leadership ▁of ▁the ▁Polish ▁king ▁Jan ▁III ▁Sob ies ki . ▁In ▁the ▁decis ive ▁Battle ▁of ▁Vienna ▁( 1 6 8 3 ), ▁the ▁Holy ▁League ▁succeeded ▁in ▁inf lic ting ▁a ▁defeat ▁on ▁the