In the 60s and 70s, there was a thread of Western academic thought in Marxist circles that mapped connections between traditional leftist narratives like the exploitation of labor to things like race and gender. Of course, socialist feminism has a longer history, and can be traced back to the early 20th century. It's debatable how much influence the academics had, beyond their simple existence adding some weight to the previously only political movement.

Within those circles, it seems they like to think of it as extending Marxism to include feminist (and race-related) thought. Having read (only) a bit of it, I'd probably say the connection is a little forced and fraught with motivated reasoning. Though Marx criticized colonialism, I read him as more focused on its relationship with the capitalist system, exploitative by his measure at home as well as overseas. Furthermore, on race, Marx (and Engels) wrote some things that would be hard to utter in polite company today.