The consensus among historians is that the Colombus family hailed from the coastal region of Liguria, and that explorer Christopher Colombus himself was born and spent much of his early years in Genoa before moving with his father to Savona at the age of 19. Despite his Genoese origins not having been controversial during his own lifetime or for centuries thereafter, the ethnic or national origin of Colombus has become the subject of much speculation during the 19th and 20th centuries, in what came to be known as the Colombus Question. Many European authors proposed alternative origins for Colombus, motivated largely by a nationalistic desire to claim his heritage for their own countries. Christopher Colombus seemed to refer to Genoa as his homeland in his own writings, and his Genoese origin can also be inferred from a biography written by his son Ferdinand Columbus. Historians have since catalogued numerous records, documents and literary references associating Colombus with Genoa.