"Let me tell you about the Barrayaran Vor," cut in Miles. "The loonies who sought a glorious death in battle found it very early on. This rapidly cleared the chain of command of the accumulated fools. The survivors were those who learned to fight dirty, and live, and fight another day, and win, and win, and win, and for whom nothing, not comfort, or security, not family or friends or their immortal souls, was more important than winning. Dead men are losers by definition. Survival and victory. They weren't supermen, or immune to pain. They sweated in confusion and darkness. And with not one-half the physical resources Marilac possesses even now, they won. When you're Vor," Miles ran down a little, "there is no mustering out."
―Miles explains how to defeat Cetagandans to a Marilacan[src]
Lord Vorloupoulos had been undergoing a slow execution for maintaining an army right before the invasion; he was released to fight the Cetagandans but would have been expected to return and complete his execution. Instead he died in battle.
Prince Xav Vorbarra was in charge of rounding up off-planet weapons and drumming up galactic support against the Cetagandans.
Horses, normally used as cavalry, were eaten during the worst winter of the war.
Babies born of a Cetagandan and a Barrayaran were usually killed by Barrayarans and sometimes their bodies were hidden in places where Cetagandan soldiers would find them.
The seventh Count Vorbretten's wife had a son by a high-ranking Cetagandan ghem instead of by the Count. This appears to have a result of a voluntary and extended relationship, rather than by force.
Vordarian's District was relatively untouched during the war, being one of the few that the Cetagandans left by treaty. The Cetagandans had built facilities there.
It lasted about twenty years, and cost the Barrayarans approximately five million lives.
Five Cetagandan ghem-generals in succession were put in charge of the war; the final one was ghem-General Yenaro, who ended up receiving all the credit for losing the war.
The Cetagandan Star Creche had a group of haut women on Barrayar who performed a gene survey of the Barrayarans in hopes of finding some novel mutation or set of mutations that could be brought into their own. They concluded that six hundred years was too short a time to find such. A large cache of treasure was stored in one of their labs when the Cetagandans fled from Barrayar.
Many of the Cetagandan leaders were executed after the war by their emperor. Officially this was for losing the war; unofficially it was for planning to wipe out the Barrayaran people with a locally-designed plague.