Chuck Foreman's 1975 season and Robert Smith's 2000 season were the two best running back seasons in Minnesota Vikings history.
In 1975, in a 14 game season, Chuck Foreman rushed for 1,070 yards and 13 touchdowns, and also caught a league-leading 73 passes for 691 yards and 9 touchdowns. His 1,761 yards from scrimmage and 22 total touchdowns in 14 games made him a major star for the 12-2 Vikings.
In 2000, Robert Smith set the Viking single-season rushing record with 1,521 yards. He averaged 5.2 yards per rush, and totaled 1,869 yards from scrimmage and 10 total touchdowns for the 11-5 Vikes.
And now there's Adrian Peterson. Perhaps his 2007 season (1,341 yards rushing, 5.6 yards per rush, 1,609 yards from scrimmage and 13 total touchdowns, games of 224 and 296 rushing yards) tops Foreman's and Smith's best seasons, perhaps not. But his 2008 season is on its way to being the best season a Viking running back has ever had. Through nine games he has 1,015 rushing yards (112.8 yards per game and 4.9 yards per attempt) and six 100 yard games. If he keeps up that pace and helps the Vikings make the playoffs, he'll not only have the greatest RB season in Viking history--he might join Alan Page (AP MVP in 1971) and Fran Tarkenton (AP MVP in 1975) as the third Viking to win league MVP.