We did not need Einstein's theories to get there. Taking relativistic effects into account would only correct us by a few centimeters or so. We, of course, also needed all of the extensions of Newton's laws, i.e. all of the mechanical engineering, aerodynamics, etc. that would allow the spaceship to be structurally sound, so you also need to bring the equations of material mechanics into things. Also, thermodynamics had to be involved. Fluid mechanics for the aerodynamics, almost a century of telecommunications technology. So I'd say you can't break it down to just Newton's laws. We stood on the shoulders of many more giants to go to the moon.
If you're talking only in terms of orbital mechanics, though, no, no relativity was used. Newton's equations are good enough (though I'm sure we utilized mathematical methods introduced long after Newton to solve those equations).