Captain Janeway: Kathryn Janeway took command of the U.S.S. Voyager in 2371, and her first mission sent her to the far side of the galaxy. It took several years for the ship to make its way home from the Borg-infested Delta Quadrant.
Seven of Nine: Annika Hansen was assimilated by the Borg at the age of six, and designated Seven of Nine. She was assigned to the U.S.S. Voyager nearly 20 years later, when the Borg required assistance to defeat Species 8472.