Marilac
Occupied by the Cetagandan Empire; eventually regained its independence, thanks in part to covert Barrayaran aid. Never seen firsthand in the saga. Marilac goes through all three phases in the course of the series. Pre-invasion, a Marilac ambassador scoffs at the notion of a Cetagandan invasion in one book. The next time we meet Marilac characters, they are POWs and their planet is under occupation. Finally, we learn of Marilac's liberation in the news.
Read more about this topic: List Of Vorkosigan Saga Planets