Celebrity

Jarl Hæsteinn of Montaigu (867, Great Adventurers) starts at Illustrious - one fame level from the cap. Fame comes fastest from creating titles and winning battles, and as a Norse raider he does both for a living. Stack monthly prestige, conquer, create duchy and kingdom titles, and don't torch your progress by breaking truces or losing wars. Saint is the same grind in piety flavour.