s ▁reign ▁was ▁relatively ▁short . ▁Bened ict ▁XVI ' s ▁own ▁reign , ▁which ▁ended ▁with ▁his ▁res ignation ▁on ▁ 2 8 ▁February ▁ 2 0 1 3 , ▁also ▁last ed ▁less ▁than ▁ 8 ▁years ▁( he ▁was ▁already ▁ 7 8 ▁when ▁elected ). ▁ ▁Saint ▁Peter ▁was ▁the ▁first ▁Pope ; ▁no ▁Pope ▁of ▁Rome ▁has ▁chosen ▁the ▁name ▁Peter ▁II , ▁although ▁there ▁is ▁no ▁prohib ition ▁against ▁doing ▁so . ▁Since ▁the ▁ 1 9 7 0 s ▁some ▁ant ip op es , ▁with ▁only ▁a ▁min usc ule ▁following , ▁took ▁the ▁name ▁Pope ▁Peter ▁II . ▁ ▁Probably ▁because ▁of ▁the ▁controvers ial ▁fif teenth - century ▁ant ip ope ▁known ▁as ▁Pope ▁John ▁XX III , ▁this ▁name ▁was ▁avoided ▁for ▁over ▁ 5 0 0 ▁years ▁until ▁the ▁election ▁in ▁ 1 9 5 8 ▁of ▁Pope ▁( of ▁Rome ) ▁John ▁XX III . ▁ ▁Im medi ately ▁after ▁John ▁XX III ' s ▁election ▁as ▁po pe ▁in ▁ 1 9 5 8 , ▁it ▁was ▁not ▁known ▁if ▁he ▁would ▁be ▁John ▁XX III ▁or ▁XX IV ; ▁he ▁decided ▁that ▁he ▁would ▁be ▁known ▁as ▁John ▁XX III . ▁The ▁number ▁used ▁by ▁an ▁ant ip ope ▁is ▁ignored ▁if ▁possible , ▁but ▁this ▁is ▁not ▁possible ▁if , ▁by ▁the ▁time ▁someone ▁is ▁reck oned ▁as ▁ant ip ope , ▁the ▁name ▁has ▁since ▁been ▁used ▁by ▁one ▁or ▁more ▁legit imate ▁pop es ▁(