our senior brains have a QUESTION

I am writing this on the blog, hoping Per and others, who may know the answer, are reading this. Hillary and i were talking several days ago about when Europe expanded their land by grabbing countries in Africa and in other parts of the world. It was in the early 20th century. So we are going nuts trying to remember the term used for this. it isn't "manifest destiny", that was our own USA's western expansion after the Louisiana purchase. But how is it referred to? Is it just "imperialism" or "colonization"? we think there is a two word expression used to embody the sense of arrogance about it.
Do not ask me how it came up, we can't remember that either and were trying to!
It's just a car discussion. i may have been mentioning Denmark and Greenland, as depicted in Smila's Sense of Snow.
o.K., Per, what is the answer????