Siege of the Inner Colonies

The Siege of the Inner Colonies was the series of engagements taking place in humanity's Inner colonies that made up the late Human-Covenant War.

Battle
From June 1, 2536 onwards, the Covenant would press into the Inner Colonies.

Eight years afterward, the Inner Colony of Miridem would fall to the Covenant. This would eventually result in the capture of Catherine Halsey. In May 2545, Actium was discovered by the Covenant, resulting in the month long Battle of Actium.

In May of 2552, the colonies of Troy and Harmony in the Hellespont system were attacked.

Attacks in the Epsilon Eridani system
On July 23, 2552, the Fleet of Valiant Prudence deployed Sangheili Zealots to disable the Visegrád Relay, effectively cutting Reach off from the UNSC.

By August 30, 2552, nearly a dozen Inner Colony worlds were passed over by the Covenant in order to attack Reach.

Aftermath
A number of Inner Colonies managed to survive the war.

The Lesser Ark
The joint UNSC and Sangheili forces were deployed to the Ark after discovering the portal.

2544

 * The Third Fleet of Glorious Consequence attacks Miridem. Dr. Halsey is captured while evacuating the planet.
 * The Third Fleet of Glorious Consequence is trapped in a stellar magnetic field, preventing them from leaving Ascon via slipspace. The UNSC, unwilling to let Dr. Halsey fall into enemy hands, enacts Operation: WARM BLANKET to recover her.

2545

 * January 10, 2545: The Covenant arrive in the Draco system and quickly destroy the UNSC defenses surrounding Draco III. However instead of using their typical tactic of glassing all major settlements, the Covenant spare some of the cities of Draco III from destruction for use as a hunting ground to feed their starving Unggoy and Kig-Yar populations. Spartan-IIs retaliate by killing every Covenant remaining on the planet, at the expense of being unable to save any civilians.
 * May: A month long campaign on Actium takes place between the Covenant and UNSC. The UNSC is defeated and the planet is eventually glassed by the Covenant, but not before the UNSC forces destroy three of the largest Covenant staging areas on record.
 * July 3, 2545: Operation: TORPEDO is undertaken by UNSC Spartan-IIIs to eliminate a Covenant fuel refinery. The refinery is destroyed, at the cost of all but two of the 300 Spartan-IIIs.

2546

 * The Covenant return to Camber in full force, bypassing the UNSC's early warning systems and quickly destroy it.
 * New Llanelli is attacked and glassed.
 * September 21, 2546: The Battle of Sargasso takes place.

2547

 * Skopje is attacked by the Covenant.

2548

 * The Battle of Meridian begins.

2549

 * Algolis is quickly invaded and destroyed by the Covenant.
 * Estuary is destroyed by the Covenant.
 * Paris IV is attacked and glassed by the Covenant.
 * September 9, 2549: The Covenant return to Arcadia, and it is quickly glassed by an overwhelmingly large fleet.

2550

 * Minab is glassed by the Covenant.

2551

 * Concord is attacked by the Covenant, but are repelled by UNSC forces.

2552

 * January 8: Operation: FIRESIDE commences on the planet Ariel. A rare tactical victory occurs and the planet is left unglassed.
 * April 22: Fumirole is attacked by the Covenant.
 * May: The Massacre of Troy in the Hellespont system takes place.
 * July 17: The Covenant are detected on approach to Sigma Octanus IV. The battle is fought and concluded on the following day with Sigma Octanus IV remaining unglassed, but the Covenant now in possession of a Forerunner artifact and having tracked at least one UNSC ship.
 * July 25: The Visegrád Relay is taken down by Covenant Zealots, beginning the Fall of Reach.
 * Mare Erythraeum is attacked by the Covenant.

Unknown

 * Imber is attacked by the Covenant. Operation: DEVIL FREEDOM takes place there.
 * Ballast is attacked at an unknown point.