There had been only three small engagements in which the UNSC fleet had decisively defeated the Covenenat. And not since Andmiral Cole had retaken Harvest colony had there been an engagement on this scale.
What were these three engagements? Obviously the Harvest engagement, but what were the other two? Does this include the battle that had just occured? Did the first engagement at Sigma Octanus IV count? (where Keyes executed the Keyes Loop)?
I realize this is a list question, but it is an on-topic one, as it is answerable by a closed list