The origin of this name is still today quite uncertain. The theories include: 1) From the Germanic “Alfher” (from which Alvaro) or the Old Norse “Áleifr” from the Proto-Norse “*AnulaiƀaR” (from which Olaf). 2) From the Latin “ŏlīva” (olive, a symbol of peace, religious piety or victory), referring to the fruit or the branch of the olive. 3) A third hypothesis, less accredited, is from the Mycenaean Greek “élaiwon (ἔλαιϝον)”, Classic Greek “Elaion (ἔλαιον)”. The names "olaf" and "oliver" are linked to the Latin root, but related to the Germanic and Norse, from (Alfher) and (Ólæifr). Saint Oliver Plunkett (1629–1681) was the Roman Catholic Archbishop of Armagh and Primate of All Ireland who was the last victim of the Popish Plot.