All dates are in Federation Standard. To make this comprehendeble for your simply individual mind.
Early 21st century - The Borg assimilate Voyager VI.
2063 - The Borg attack the Phoenix, the first Earth based warp capable ship.
Late 23rd century - The Borg attack the El-Aurian home world, nearly driving the El-Aurians to extinction, and spreading them throughout the galaxy.
2356 - The Borg assimilate the Raven, a Federation exploration vessel, while traveling to the Delta Quadrant.
2364 - The Borg begin to remove outposts from along the Neutral Zone, reigniting conflicts between the Federation and the Romulan Star Empire.
2365 - The entity Q places the USS Enterprise in the path of a Borg vessel, in System J-25, which is 7,000 light years from Federation space. The Enterprise is saved only through the intervention of Q. Starfleet Tactical begins to prepare for an impending Borg invasion.
2366 - The Borg arrive in Federation space months ahead of schedule. The Borg assimilate New Providence, a colony on Jouret IV. The Borg destroy the USS Lalo. The Borg assimilate Captain Jean-Luc Picard of the Enterprise, transforming him into Locutus of Borg. Starfleet masses a defensive fleet of forty starships at Wolf 359. Thirty-nine of those vessels are destroyed. Eleven thousand lives are lost. Finally, Enterprise personnel are able to capture Locutus, and use his link to destroy the Borg vessel.
2368 - A Borg scout craft crashes in the Argolis Cluster. Four crew members are killed. Only one, designated Third of Five, survives. Third of Five is taken aboard the Enterprise and nursed back to health. While aboard the Enterprise, his link to the collective degrades. Third of Five befriends Lieutenant Commander Geordi LaForge. He is nicknamed Hugh. Enterprise personnel devise a plan to incorporate an invasive program into Hugh's programming, which theoretically would destroy the Borg collective. The plan is vetoed by Captain Picard as immoral. Hugh is instead returned to the collective as an individual.
2369 - Hugh's newfound individuality spreads throughout the collective. Without the reassuring voice of the collective, the Borg are unable to function. Some Borg shut themselves down. Others starve to death, now faced with the tedious at best need to consume food.
2369 - The android, Lore, discovers a Borg ship left adrift. He becomes their leader, and adopts the title of "the One." Now armed with ships of a new configuration, and transwarp conduits, the Borg attack an outpost on Ohniaka III, a Federation outpost with no strategic value. The Enterprise arrives too late to save the 274 officers assigned there. The Borg vessel escapes. The Enterprise eventually finds the ship again. Two Borg are beamed aboard the Enterprise as a distraction to allow the Borg vessel to escape through a trans-warp conduit. One is killed. The other, named Crosis, is captured. While held in the Enterprise's brig, Crosis convinces Lieutenant Commander Data, the brother of the One, to join with the Borg. Data and Crosis commandeer a shuttle craft, and take it through a trans-warp conduit, with the intent of going to a Borg compound. The Enterprise follows, and upon arriving at the compound, the crew is swiftly captured. While being held, they are able to access Data's ethics program. Data is then able to deactivate Lore.
2372 - The poison of individuality proves to have no lasting implications. The Borg attack Earth again. The cube is destroyed by the newest and best ship in the fleet, the Enterprise-E. Before the entire ship is engulfed by the explosion, the Borg cube releases a sphere-shaped escape pod. The sphere opens a temporal wake, and travels back to the year 2063. The Enterprise follows, and destroys the Borg sphere. However, several Borg beam aboard the Enterprise, and begin the efficient assimilation of crew members. Several crew members become aware of our Queen. She is terminated when Lieutenant Commander Data punctures the plasma coolant tanks.
2372 - The Borg begin the efficient assimilation of beings outside of this realm. Several beings are assimilated. One species, designated 8472, will not be assimilated. Species 8472 interprets the attempted assimilation of their race as an act of war, and in turn invade the Borg realm. In the ensuing battles, millions of Borg drones are terminated, thousands of Borg ships are destroyed, and hundreds of planets are destroyed. A vessel from the Alpha Quadrant, designated Voyager, offers its assistance. After hearing the terms of Captain Kathryn Janeway, the collective accepts. Voyager's doctor, a strange holographic projection, devises a plan to destroy Species 8472 at the cellular level. The plan is successful-- a great victory for the Borg collective. A drone, designated Seven of Nine Tertiary Adjunct of Unimatrix 01, temporarily designated Speaker for the Borg, is disconnected from the collective. It is believed that this drone still functions.