There were a lot of changes between 1570 and 1969. See
old.usccb.org/romanmissal/resources-background.shtml
It gives the major changes as
Code:
1604 – Pope Clement VIII
1634 – Pope Urban VIII
1884 – Pope Leo XIII
1920 – Pope Benedict XV
1962 – Pope John XXIII
1970 – Pope Paul VI
1975 – Pope Paul VI
2002 – Pope John Paul II
In addition, there were a number of other minor revisions to the text, published as “reprints” which incorporated minor changes. The most recent of these were in 1957 after Pope Pius XII’s revisions to the rites of Holy Week and the Sacred Triduum in 1955, and in 2008, when Pope Benedict XVI incorporated a number of additional prayers, included those for recently canonized saints as well as for the celebration of an extended Vigil for Pentecost.