If I may, I know that “settlers” is also an academic term that is generally used and it's not meant to focus only on settlers who were individuals, but again I remind you that this is a part of the preamble to provide context as to what the realities were, that there were indeed settlers and people—agents—both of whom were having negative impacts on the lives of indigenous peoples.
I think encompassing it as “the arrival of settlers and colonization” provides that context to show why reconciliation is so important.