Timeline

Over 6000 years ago

 * Rose Quartz, Ruby, Sapphire, and Pearl are "born"/created in Gem Homeworld.

6000 years ago

 * The Kindergarten is used to incubate new gems. Amethyst was made.

Over 5000 years ago

 * Rose Quartz decided to rebel against her homeworld. A battle occurs at the location which would later become the Strawberry Battlefield. Many Gem Warriors fall. Rose's scabbard is lost.

Unknown Time Period

 * The Galaxy Warp goes inactive.
 * The Crystal Temple is constructed.

Recent History

 * Ocean Town is abandoned.
 * Greg drops out of college to become a professional musician and tour the country. He records Space Train to the Cosmos.
 * Roughly two decades ago Greg falls in love with Rose Quartz and decides to stay in Beach City.
 * Greg starts growing a beard and records Let Me Drive My Van into Your Heart.
 * Roughly a decade ago, Rose Quartz records a video for Steven.
 * Roughly 12 years ago, Rose Quartz gives birth to Steven Universe.
 * Roughly 5 years ago, the Aqua Mexican restaurant goes out of business.
 * Roughly a year ago, Connie Maheswaran and Steven see each other for the first time at the annual boardwalk parade.

1st Year

 * Start of the series.
 * Ocean Gem takes place on the first day of summer, placing the events in the first half of Season 1, including Beach-a-Palooza in spring.
 * Horror Club appears to have taken place around Halloween.
 * Winter Forecast takes place during winter.
 * Maximum Capacity takes place around Beach City's annual New Year's fireworks, marking the end of the year.

2nd Year

 * Marble Madness takes place in early spring. The first spring buds can be seen on the trees around the Maheswarans' townhouse.
 * Open Book, Story for Steven and Shirt Club take place before The Return and Jail Break.