America embraced nuclear power than avoid it like we did. The U.S is very similar but different since during 1950s-1960s they started using nuclear power for cars, buildings and many things that require gas or fuel today. This obviously caused radiation in homes and was very convenient as well. Mr Handy robot was created for assistant and like a maid but simpler. At the time, America was at war with communist country China. General Atomics created the Mr. Gutsy which was the Mr. Handy but for war against China. The first Assaultron was created  RobCo and sold to the US military, with legs and powerful arms to defeat the communists. It is rumored that China created their first power armor suit at the time, called the T-45 Power Armour Suit. Power armor is a powerful and shield full suit of armor created to protect from bullets and explosion and for a better advantage and enables you to not take fall damage from a high height.

Lots of atomic bombs were launched at many parts of America's commonwealths causing a nuclear holocaust worldwide. Fallout 76 begins a few decades after the bombs drop (I'll talk about that later.) After the events of F76, 59 years later, Fallout 1 begins in California with a vault dweller being chosen to bring a water chip (A chip that fixes purified water in the game)  that the overseer of Vault 13 sends him to the wasteland. He encounters many friends and foes bu at the end acquires a water chip and takes it to Vault 13. They take it but the overseer doesn't let him in because he might be deadly from to much radiation. He sadly dies and Vault 13 gets invaded by FEV variants: 

THE SUPER MUTANTS.

In 2241 80 years after the events of Fallout 1, the primitive town of Arroyo suffers the worst drought on record. The village elder asks the descendant of the Vault 13 Dweller, referred to as the Chosen One, to retrieve a Garden of Eden Creation Kit (GECK) for Arroyo. The Chosen One finds Vault 13, the supposed location of a GECK, devoid of the majority of its former human inhabitants and instead inhabited by intelligent Deathclaws. The Chosen One returns to find their village captured by the remnants of the Enclave. The Enclave terrorizes the inhabitants of the continental United States with their supreme arsenal of advanced technology. The Chosen One, through various means, activates an ancient oil tanker and engages its autopilot, thus allowing them to reach the Enclave's main base on an offshore oil rig. It is revealed that the dwellers of Vault 13 were captured as well, to be used as test subjects for the FEV  The Enclave modified the FEV into an airborne disease, designed to attack any living creatures with mutated DNA. With all genetic impurities removed, the Enclave (who remain protected from radiation) could take over. The Chosen One frees both their fellow villagers from Arroyo and the Vault 13 dwellers from Enclave control and subsequently destroys the Enclave's oil rig, killing Dick Richardson, the President of the United States and Frank Horrigan in a victorious battle same as exploding the oil rig. Also I forgot to mention that the Chosen One drives around a car and that it's the only Fallout game that has this mechanic.

Helpful Sources: Google, Wikipedia.

Fallout 3 begins in Washington D.C, Northern Virginia and parts of Maryland too. 200 years after the bombs dropped. This game has the term "Capital Wasteland" for it's location.  After the Lone Wanderer's 19th birthday, their father, a scientist named James, inexplicably leaves the Vault. The Vault Dweller decides to track down their father, and journeys the region in and around Washington, D.C., now known as the Capital Wasteland. Along the way, the Lone Wanderer learns about their father's background from other characters, including the residents of Megaton, a radio DJ named Three Dog, and a scientist named Madison Li. Before the Lone Wanderer's birth, James and his wife Catherine had been working on Project Purity, in which a water purifier built in the Jefferson Memorial would have purified the irradiated water in the Tidal Basin and Potomac River. James reveals that he left Vault 101 to seek the G.E.C.K. The Lone Wanderer find the G.E.C.K in Vault 87 but get captured by the Enclave and put in a base. The player has an option to leave peacefully or destroy it. Lone Wanderer gets help from the Brotherhood of Steel, a military organization that protects the residents of the Capital Wasteland. Lone Wanderer learns that the purifier needs to be manually activated but is filled with radiation by James and needs to sacrifice himself, have someone else do it or let it explode. Sources: Wikipedia

Fallout New Vegas begins in 2281, 4 years after the events of FO3. While delivering a storage device known as the Platinum Chip to New Vegas, the courier (Main character) is ambushed by mobster and casino owner Benny, who steals the Platinum Chip and shoots them. Left for dead, the courier is dug out by securitron Victor and nursed back to health by physician Doc Mitchell. The courier then departs on the search of Benny and the Platinum Chip. In the casino on the New Vegas strip, the courier confronts Benny, where they choose to either kill Benny and recover the Platinum Chip or let him escape. Mr House wanted the platinum chip to defend and protect New Vegas with upgrading securitrons but Benny wanted to take over by a reprogrammed securitron called Yes-Man. The courier has a choice to pick a side, Caesar's Legion or NCR for the battle of Hoover Dam. The player has a choice to go with Mr. House's plan to control New Vegas alone or to leave it independent. The Mojave Wasteland is left to the Couriers decision.

Fallout 4 begins in Boston, Massachusetts in 2077. The players plays as a war veteran named Nate or a Law Doctor named Nora. You can customize your facial features, gender and body too. You go to the vault right as the bombs dropped and enter a cryogenic chamber to freeze until after the bombs dropped. A man named Kellogg (Yeah the cereal brand haha.) kills your wifes and takes your newborn son. You come out the vault in 2287 and meet some friends to find your son. You meet up with a detective and a doctor to find a super mutant that helps you go to the Institute and confront him by the help of either the Brotherhood of Steel, Minutemen or Railroad. You find out that he is the reason the commonwealth is shook by the Institute. You have a choice to side with them or explode the building, which is the most ideal option for the game. This is my favorite Fallout game.

Fallout 76 isn't really that much of story, It's more of a multiplayer game but It is set before the storyline of fallout 1. And Is really cool but sometimes annoying when people kill you a lot, you can also play pacifist. That concludes most of the timeline. It takes place in West Virginia and you play as a vault dweller in vault 76 (a control vault) during Reclamation Day which is basically vault dwellers making the world a better place.  Vault 76 is one of only 13 vaults that were actual vaults and not demented experiments set up by Vault-Tec. But the graphics are amazing since this is the most recent Fallout game. The game also includes new undiscovered power armor types ranging from working to Secret Service types!