Facts are hard, Rosie.
Settlers and immigrants have some key differences, including the nature of their movement, their goals, and their relationship to the land:
Movement
Immigrants tend to move as individuals or families, while settlers often move in groups.
Goals
Immigrants usually want to join an existing society, while settlers often want to replace it and establish their own society.
Relationship to the land
Settlers may travel to discover new land, or to areas that are previously uninhabited or sparsely populated. They may also come armed with weapons and a nationalist agenda, and may engage in the violent dispossession of the original inhabitants. Immigrants, on the other hand, may arrive in a territory through an orderly and lawful process.