The Second Great War follows the events of, in particular the canon Allied campaign. The Allies were ultimately victorious at the end of the war, and the leader of the Soviets during that time, Stalin, was killed.
- The United States began their American Crusades and occupied Russia, Latin America and Africa. However, their occupation did not last.
- Socialist revolutions spread across Latin America with support from Russia, eventually leading into the formation of the Latin Confederation.
- The Europeans left their colonies in Africa due to the devastation of the war, while the Americans took over the continent as occupiers. These actions led into the founding of the Scorpion Cell to enact their "war of resistance".
- Alexander Romanov succeeded Stalin as Premier.
- Yuri, a remnant of Stalin's psychic legacy, was appointed as Chief Advisor of Romanov. PsiCorps was also founded.
- Volkov and Chitzkoi's remains were acquired by the Soviets. Eventually the cyborg duo was resurrected.
- Volkov's official description and the briefing from the mission Archetype also mentioned that he went berserk, a reference to the mission in .
- Colonel retake Soviet-occupied Athens. is retired during the Third Great War, and asked two European commanders to
- Professor Albert Einstein would not live long enough to see the Third Great War. Furthermore, he stopped development of the Chronosphere as he deemed that meddling with the forces of time and space is dangerous and unethical. However, he left clues behind in case the Chronosphere was needed again.
- While the Chronosphere invention was improved by SteinsTech, the original device still existed. Initially the Soviets acquired the device during the Third Great War, then the Epsilon Army later stole it from them during the Mental Omega War, which they have put to great use twice.
- Most of the arsenal used by both factions have been abandoned in several battlefields. However, many of these abandoned vehicles in the campaign can be commandeered through Engineers, such as the missions Think Different and Dawnbreaker.
- Before and during Act 1, some equipment from the previous war are still actively used but not produced, particularly by the separatists.
Official description mentions
According to their respective lore in the official website and in-game, several units in Mental Omega directly succeeded those featured in Red Alert 1. These units are the following:
- The Guardian GI. became the
- The continued.
- The Chrono Miner and War Miner for the Allies and Soviets respectively. became the
- The Humvee. became the
- The Bulldog Tank. became the
- The Cavalier Tank. became the
- The Zephyr Artillery. became the
- The Warhawk. became the
- The Hazequad. became the
- The Trident Battleship. was modernized and became the
- The Quickshifter. Furthermore, the phase technology was stolen and used for the Shadow Tank.  and became the
- The Pyro. became the
- The improved. was
- were rebuilt. and
- The Qilin Tank. became the
- The Scud Launcher. became the
- The modernized with former warheads. was
- The Tesla Cruiser. became the
- The Akula Missile Sub. became the
- The Apocalypse Tank and Super Apocalypse Tank. (and by extension the became the
- The M.A.D.M.A.N. was improved and became the
- was planned to be a prequel to the original (which could have explained the background for some of the more outlandish technologies seen in the latter). However, this idea was complicated after the release of by Westwood Pacific, which led the Red Alert universe to an entirely different storyline. The main Westwood studio in Las Vegas attempted to remedy this with and , but Westwood Studios were closed before these projects could reach a serious development phase. Hence, the Red Alert universe can be seen as separate to the Tiberium universe, but the connection to the Tiberium universe after the Allied ending in the first Red Alert can also be considered an alternate timeline. On the , the latter approach is considered valid, unless otherwise stated.
- in the Command & Conquer Wiki