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.

The Battle for Arcadia was a battle for the colony Arcadia in the Procyon system, which occurred in the immediate aftermath of the Harvest Campaign.

The Battle of the Etran Harborage was a battle between the UNSC Spirit of Fire and Covenant forces lead by Arbiter Ripa 'Moramee on Shield World 0459, also known as the Etran Harborage.

The Fall of Reach was possibly the largest battle during the Human-Covenant War, taking place in the Epsilon Eridani system, in orbit and on the ground of Reach, humanity's largest military stronghold.

The Battle of Installation 04 was an engagement between the UNSC Pillar of Autumn and the Covenant Fleet of Particular Justice on and around the Forerunner megastructure known as Installation 04, or Alpha Halo, in the Soell system.

The Battle for Earth was a large-scale space, air, and ground battle between the invading Covenant forces and the UNSC Home Fleet on and around Earth at the end of 2552.

The Battle of Installation 05 was an engagement between the Covenant forces, including those that fled the Battle for Earth, High Charity, and the Second Fleet of Homogeneous Clarity, and the UNSC-allied forces, including the UNSC In Amber Clad led by Miranda Keyes, and the Fleet of Retribution led by the Arbiter Thel 'Vadam.