The Callisto Incident was a series of events involving the UNSC Callisto that is considered the first true insurrectionist attack from January to March 2494. 

The Second Battle of Harvest, also known as just simply the Battle of Harvest, was humanities first attempt to recover the planet Harvest from the Covenant, who wiped out the existing colony and killed tens of thousands of civilians a year earlier.

The Harvest Campaign was a five-year campaign to retake the planet Harvest after the Covenant took over the planet and wiped out the colony on Harvest.

Operation: SILENT STORM was a UNSC operation to use EVA tactics to infiltrate Covenant vessels and either capture or destroy them from within early in the Human-Covenant War in March and April 2526.

The Battle of Alpha Aurigae was a large naval battle between UNSC and Covenant forces in the Origami Asteroid Field of the Alpha Aurigae system, culminating in a UNSC victory. 

The Battle of XI Boötis A was a naval battle during the early portions of the Human-Covenant War.

The Battle of the Great Bear was a naval battle between a UNSC fleet of seventeen warships and three Covenant warships in the Groombridge-1830 system.

In an effort to limit the ability for the Covenant to discover human colonies, including the inner colonies and Earth, the Cole Protocol was established to wipe all ship navigation data when the UNSC came into contact with any Covenant forces.

The Battle of Leonis Minoris was a battle between Covenant and UNSC forces in the Leonis Minoris system sometime in 2537.

The Battle of Psi Serpentis was a major conflict between a UNSC fleet of 162 warships led by the UNSC Everest and Admiral Preston Cole and two fleets of Covenant warships totaling over 300 ships in the Psi Serpentis system in April 2543.