The hugely successful series, which stars Dame Maggie Smith and Hugh Bonneville, collected one the main awards at the event, which celebrates the best in British TV.
Dr Who was also a big winner - the sci-fi series' stars Matt Smith and Karen Gillan took home prizes for Top Male and Top Female performances
Simon Cowell's The X Factor was named Best Talent Show for a third year running, and TV favourites Anthony McPartlin and Declan Donnelly broke National Television Awards records when they picked up the Best Entertainment Presenter(s) for an 11th successive year.
Comedian Alan Carr won the Best Talkshow prize for his popular Chatty Man series and the cast of Britain's longest running soap, Coronation Street, paid a special tribute to late actress Betty Driver, who passed away last year (11). Driver was a regular on the show for 42 years. The soap also took home the Best Serial Drama honour.