2069

Events

The Earth colony ship SS Conestoga is launched with the mission of colonizing the planet Terra Nova. (ENT: "Terra Nova")
Approximate – The Emperor of the Klingon Empire dies without any successors claiming the throne. This results in the Klingon High Council taking effective political control of the Empire. (TNG: "Rightful Heir")
Intersat code, a form of interstellar communication for Earth spaceships, is discontinued. (TAS: "The Terratin Incident")
The last of the Kzinti Wars ends around this year with a Human victory. (TAS: "The Slaver Weapon")
At the peak of their empire, a Skorr philosopher named Alar starts the process of reforming his society into a nation of pacifists. (TAS: "The Jihad")

The TNG version of 21st century history states that World War III took place in the 2050s, and the post-atomic effects were recorded in the 2060s and 2070s in Star Trek: First Contact and "Encounter at Farpoint". It seems that a high profile, well-outfitted colonization effort using the infant warp drive technology came from this turmoil. The version of events presented in Enterprise relates well with the launch of SS Valiant only two years after First Contact.

According to ENT: "Terra Nova", at that time, Humans already built New Berlin on the Moon, Utopia Planetia on Mars, and even a few asteroid colonies, but all within our solar system. According to Star Trek: Star Charts, on page 39, Utopia Planitia Base was indeed founded on Mars in 2069. VOY: "The 37's" indicates that Mars was fully colonized by people from Earth in 2103.