This is the Ninjago timeline on my opinion. You don't have to agree with everything.

10000 BC: The First Spinjitzu Master creates Ninjago.

10000 BC: The FSM battles and defeats The Overlord.

10000 BC: The FSM creates the Realm Crystal and brings The Serpentine from Chima.

1956: Yang creates Airjitzu.

1958-9: Wu and Garmadon are born.

1960: The Green Ninja Prophecy is written.

1961: Garmadon is bitten by the Great Devourer.

1962: Nadakhan creates his crew.

1962: Captain Soto and Nadakhan battle and Soto wins the fight.

1962: The Destiny's Bounty shrinks killing Soto and his crew.

1975: Dr. Julien builds Zane.

1976: Wu and Garmadon defeat Samukai.

1976: Garmadon begins training under Chen.

1976: Wu begins training Morro.

1976: Morro leaves Wu but dies in the Caves of Despair.

1977: Wu defeats villains such as Kirchonn the Invincible and the Time Ninja.

1977: The Serpentnie War breaks out.

1977: The Elemental Masters defeat the Serpentine using the Scared Flutes.

1977: The Anacondrai Generals are banished to the Cursed Realm

1977: Acronix and Krux betray the Elemental Alliance, but are defeated with the Time Blades.

1978: Krux escapes the Time Vortex. 

1978: Ray and Maya find the Reversal Time Blade and hide it in the Boling Sea.

1999: The First Spinjitzu Master leaves a secret messege about his tomb to Wu in his staff.

2000- The Ninja are born.

2001: Lloyd is born.

2001: The First Spinjitzu Master dies.

2001: Yang turns himself and his students into ghosts with the Yin Blade.

2001: Garmadon turns evil and is banished to The Underworld where he takes over from Samukai.

2010: Wu wisits Dr. Julien and meets Zane for the first time.

2010: Dr. Julien dies.

2010: Wu hides the Golden Weapons, makes a map and gives it to Ray.

2010: Krux kindaps Ray and Maya.

2011: Samukai resurrects Dr. Julien and the later degsines wehicles for him.

2011: Samukai imprisons Dr. Julien in a lighthouse and places a Leviathan to guard him.

2011: Dr. Julien builds Echo Zane and Tai-D.

2011: Garmadon frees some of Wu's old enemies and orders them to defeat Wu.

2011: Wu invites Kai, Jay, Zane and Cole to his Ninja Team.

2011: Lord Garmadon leads a hunt for the Golden Weapons.

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