Chronological order on X-Men movies.
3000 B.C - Apocalypse made the pyramids in Ancient Egypt
1832 - Wolverine was born (X-Men Origins: Wolverine)
1861-1865 - James Howlett and Victor Creed fight in Civil War (X-MO:W)
1917-1918 - WWI (X-MO:W)
1944 - Erik Lehnsherr is taken to Auschwitz
1962 - X-Men First Class (Cuban Missile Crisis)
1969-1971 - James & Victor fight in Vietnam (X-MO:W)
1972 - Logan quits Team X
1973 - Is where Wolverine was sent in Days of Future Past
(So, that's when things get a bit messy)
1973, January 27
- Mystique assassinates Bolivar Trask in Paris.
- Trask Industries unveils the Sentinels Program.
- Sentinel: Mark I are created. Between 1973 and 1996, Trask Industries produces 8,732 Mark I Sentinels for the governments of the United States, China, Russia, Israel, Saudi Arabia, France, India and the United Kingdom.
- Erik Lehnsherr is publicly revealed as having participated in the John F. Kennedy assassination 10 years previously.
1979 - The Rest of XMO:W (leading up to the Three Mile Island Accident)
March 28 - Logan loses his memory
1986 - Charles Xavier and Erik Lehnsherr visit Jean Grey. (XM:TLS)
1996 - Young Angel cuts off his wings (XM:TLS)
2003 - Rest of X-Men (X-Men, X2: X-Men United: The Movie Prequel: Wolverine, X2: X-Men United: The Movie Prequel: Nightcrawler, X2: X-Men United.
2005 - X-Men: The Official Game (So yeah, the video game is also connected with the movies)
2006 - X-Men: The Last Stand
2011 - Angel is killed by Sentinels during an Occupy Wall Street march on the X-Mansio (X-M:DoFP)
2013 - The Wolverien
2015 - Professor X and Magneto meet Wolverine at an airport.
- Beast is killed by Human Majority protesters. (X-M:FC)
2023 - The X-Men send Wolverine back in time to stop Mystique from killing Bolivar Trask.
2030 - According to Trask Industries projections, homo sapiens may become extinct due to mutation.
1973, January 27
-The X-Men prevent Mystique from killing Bolivar Trask in Paris.
-Trask Industries unveils the Sentinels Program.
-Mystique spares Bolivar Trask at the White House.
-The Sentinels Program is cancelled. Bolivar Trask is arrested for selling military secrets.
-Mystique, under the guise of William Stryker, raises Logan from the Potomac River.
1983 - Apocalypse resurfaces
2023 - The X-Men (including Jean Grey and Cyclops) are all present at the X-Mansion.
2020 - Deadpool
2023 - The ending of DoFP (The future Wolverine wakes up form his time traveling adventures and finds that Jean Gray and Cyclops are alive. Future Xavier helps Wolverine to catch up what he missed out on since 1973.
2029 - Logan