In what year did 'Roots' win the Emmy Award for 'Best limited series'?

The 'Roots' miniseries aired in January of 1977 and won the Emmy that year for Best Limited Series.

It also won Emmys that year for :

Best Actor - Drama or Comedy Series, Single Appearance (Lou gossett, Jr.)

Best Director - Drama Series (David Greene for "Part I")

Best Editing - Drama Series (Neil Travis for "Part I")

Best Music Composition for a Series - Dramatic Underscore (Gerald Fried & Quincy Jones"Part I")

Best Sound Editing - Series

Best Supporting Actress - Comedy or Drama Series, Single Appearance (Olivia Cole for "Part VIII")

Best Writing - Drama Series (Ernest Kinoy & William Blinn for "Part II")