1962 X-Men: First Class

Cuban Missile Crisis , 1962

1973 X-Men: Days of Future Past

1973 is clearly stated in film.  This is after Wolverine left
Stryker's group, but before his "lumber-jack" job.  This film is  
in the middle of "X-Men: Origins: Wolverine" and start with an alternate 
timeline that ends up never existing because a new timeline is put in place.

1970-80 X-Men: Origins: Wolverine

This covers Wolverine's past, but takes place 
during Vietnam and through the 1970's up 
until 3-Mile Island ( 1979 ).
Wolverine's MIND is WIPED and he is ENCAGED as 
"WEAPON X"

1984 X-Men: Apocalypse

Wolerine (Weapon X) is RELEASED from his CAGE, about
15-years before the 2000 X-Men film, and
Jean restores a few of Wolerine's memories.

2000 X-Men 2003 X2 2006 X-Men: The Last Stand 2013 The Wolverine

This is after the "X-Men: The Last Stand" film.

2016 Deadpool