Precessing of the Earth
The Wikipedia Precession article explains this.

Precession of the Earth's axis is caused mainly by the Sun's gravity acting on the oblate spheriod of the Earth. The Earth bulges at the equator and the force of the Sun's gravity on the bulge makes the axis wobble like a child's spinning top - the axis traces out a cone shape in space. It has no effect on the Earth's orbit. 

Perihelion precession is caused by the gravity of Jupiter and the other outer planets.