He was born in Falaise, Normandy, around 1028.
Because he CONQUERED England. "Conqueror" is just a nick-name that stuck :) Like Edward I - Longshanks XD
William Robyns's birth name is William Robins.
William Roerick's birth name is William Roehrich.
William Sheller's birth name is William Hand.
William Terriss's birth name is William Lewin.
William Spiritdancer's birth name is William Drake.
William Dalphin's birth name is William Dalphin.
William Markus's birth name is William Marcus.
William Marr's birth name is William Dobie.
William Lanteau's birth name is William Lanctot.
William DuFresne's birth name is William Petty.
William Ilkley's birth name is William Brown.