Sonic's World

Mobius is the homeworld of the Mobians, Overlanders and humans. Recently it was discovered that Mobius is actually a future version of Earth (in an alternate dimension). According to this universe's timeline, Earth's year would be approximately 14,016 CE, with Mobius' calendar year at 3238. It is still unknown exactly what was the starting point for their calendar, but its was likely calculated using what the Echidna Tomes call the Days of Fury.

Prehistoric
Approximately 12,000 years ago, during the 21st century of the "old world" when Mobius was still known as "Earth", an alien race known as the Xorda came to the planet to offer an alliance to its human population. However, the emissary they dispatched was captured, studied and subsequently dissected by a group of scientists led by Ivan Kintobor, a leading scientist at the time. Ivan had hoped to use the captured alien and its technology to produce the robot Isaac as well as numerous other creations. His methods however proved antagonistic towards the Xorda. In retaliation, the aliens bombarded the planet with Gene Bombs with the intention of exterminating all life on the planet. The bombs had an unforeseen side effect however. The human population underwent a de-evolution, forming the four-fingered Overlanders seen on Mobius today, while the rest of the animal kingdom experienced a rapid evolution, forming modern-day Mobians. (StH: #125, #148)

Early History
Approximatly 10,000 years ago, the planet suffered a massive environmental cataclysm. The Gene Bombs were supposed to preserve Earth's environment as it was when it was attacked. However, their interaction with the planet caused massive volcanic reactions, hurling billions of tons of ash and dirt into the air. This is what is chronicled as the First Day of Fury in Echidna theology. The Days of Fury continued to affect Mobius for thousands of years, right up to modern day. The Echidna Tomes describe them as "natures way of adjusting to environmental changes it undergoes over a certain duration" according to Athair. Prior to the Day of Fury which happened in the year 3235, Athair stated the last recorded Day of Fury happened some "twelve hundred years ago". (StH: #148, KtE: #12)

Shortly after this caraclysm, the event known as the Coming of the Chaos Emeralds (which lead to the extinction of the Mobosaurs) occurred - a direct result of the Gene Bombs' radiation blending with beryl deposits deep within the planet's surface. This gave birth to the omnipotent beings known as the Ancient Walkers and provided immortality to Mammoth Mogul. (StH: #148, TMS: #3, KCX)

Approximately 9,000 years ago, the Echidnas were already well developed. The Albion Knights of Aurora found themselves defending the planet against the wizard caste known as the Order of Ixis, which was bent on world domination and was subservient to their founder, Mammoth Mogul. Despite the Order's incredible powers, the Albion Knights successfully defeated Mogul during the Forgotten War, effectively wiping out all of the Order of Ixis but him and three members, the latter merged to form the individual wizard Ixis Naugus. (StH: #66, #163)

Developing Societies
Approximately 1,000 years ago, the other Mobians learned from the Echidnas on how to structure themselves into societies. One Mobian, Alexander, decided to pool the various groups resources and knowledge together to form a single society. While the Overlanders proved too violent in nature to be included, and the Echidnas chose to exclude themselves from joining the group, the other Mobians pulled together and created Mobotropolis - the first multicultural city on the planet. By this time however, the Echidnas in Albion had already ventured out into space. (StH: #71, KtE: #12)

Modern History
Approximately 18 years ago (3220):
 * The Great War between the Overlanders and the Kingdom of Acorn begins. (StH: #73, #112)
 * Sonic the Hedgehog and other future members of the Knothole Freedom Fighters are born. (StH: #112)

Approximately 13 years ago (3225):
 * The Great War ends, with the Mobians having achieved victory. (StH: #50, #78)
 * Miles "Tails" Prower is born. (StH: #112, SSS: #9)
 * Julian Kintobor (who renamed himself Dr. Ivo Robotnik) betrays the Kingdom of Acorn and begins his global takeover. (StH: #42, SSS: #9)

Approximately 3 years ago (3235):
 * Dr. Ivo Robotnik is killed when his nephew Snively changed the Ultimate Annihilator to target only his DNA structure. (StH: #50, #72)
 * Freedom Fighter groups regain control over Mobotropolis and a brief time of peace ensued. (SSS: #2)
 * Maximillian Acorn is returned to the Prime Zone and resumes his role as king. (StH: #41, SSS: #4)

Approximately 2 years ago (3236):
 * The most recent Day of Fury takes place, nearly wiping out the Lost Tribe. (KtE: #12)
 * Robo-Robotnik manages to retake Mobotropolis. (StH: #75, #76)
 * The Kingdom of Knothole is officially formed to act as a haven for those opposed to Robo-Robotnik's tyranny. (StH: #78)
 * The Xorda attack Mobius but are repelled. Sonic is transported to another part of the galaxy and presumed dead. (StH: #125)

Approximately 1 year ago (3237):
 * The Eggman Empire is officially formed. (StH: #130)
 * Dr. Eggman formally declares war on the Kingdom of Knothole and the United Federation. (StH: #130)
 * Albion is completly destroyed by the Eggman Empire after Dr. Finitevus sabotages its defenses. (StH: #182)
 * Angel Island falls to the forces of the Eggman Empire and the Dingo Regime. (StH: #130)

Current year (3238):
 * Golden Hive Colony is obliterated by the Eggman Empire with almost no survivors. (StH: #138)
 * The Ancient Walkers are killed when the dimensional barriers are breached. (StH: #162)
 * A.D.A.M. pulls all of the Chaos Emeralds in the universe to Mobius, where they are subsequently sent into the Zone of Silence by the Chosen One. (StH: #169)
 * The Eggman Empire destroys Knothole Village via aerial bombardment with his Egg Fleet. (StH: #175)
 * The citizens of the Kingdom of Acorn are rescued and transported to the New Mobotropolis. (StH: #176, #177)
 * Angel Island is liberated of its Dingo oppressors by Enerjak. (StH: #181)
 * The majority of Echidnas, (having been reduced to 10% of their former population) are relocated to Albion's former site by Enerjak. (StH: #181)
 * New Megaopolis is destroyed by Enerjak. Some surviving Echidnas, under Lien-Da, ally with Dr. Eggman. (StH: #182, #183, #184)

Continents/Island

 * Angel Island (floating)
 * Devil's Gulag
 * Downunda
 * Flickie Island
 * Mainland
 * Southern Tundra
 * Walrus Island

Cities/Countries

 * Albion
 * Echidnaopolis
 * Feral Forest
 * Golden Hive Colony
 * Kingdom of Leonus
 * Kingdom of Mercia (aka "Snottingham")
 * Knothole Village
 * Lord Khan's Village
 * Mobotropolis/Robotropolis
 * Mysterious Cat Country
 * Nerb Kingdom
 * New Megaopolis
 * MegaCentral
 * New Mobotropolis
 * Old Megaopolis
 * Station Square
 * Sand Blast City
 * Vesuvio
 * Western Continent Village

Other

 * Badlands
 * Canyons
 * Great Forest
 * Sandopolis

Measurements

 * Weight: Measured in Stone (1 Stone = approximately 6.35 Kg or 14 lbs)
 * Height: Measured in Marks (1 Mark = approximately 1.4 cm or a little over 1/2 inch)

Background Information
The exact date of the Mobian calendar is unknown. However, the year is estimated to be 3238 as Sonic has had two birthdays since the series began (year was 3235 then) and as a result of being in space for 1 year, three years have therefore gone by.