How to show a tracked video in 3D view? In the Movie Clip Editor I have tracked a video. Now when I go back to the 3D view, I can see that my camera is following the trackings, however, I can't see the video.

How can I display a tracked video in 3D View?

PS:
I'm new to Blender, so please forgive me if this question already has an answer and/or if I'm using the wrong terminology...
For the sake of completeness on this site, I am extending my comments to an answer.

To view the footage from the motion track in the camera, go into camera view Numpad 0, and then add a new background image. To do this go to the bottom of the properties panel, check background images, add a new one, and then set it to movie clip and select your clip.