Following the announcement that "Downton Abbey" – the U.K.'s most popular costume drama in television history – would end after the upcoming Season 6, some have wondered what led to the decision.

Although Gareth Neame, executive producer, explained the reasoning, the networks tried to save the show.

Apparently, executives from the British network ITV, which produced the series along with Carnival Films, attempted to persuade creator and writer Julian Fellowes to allow someone else to take over the show, according to Radio Times. Fellowes, who has written every episode, will begin work on the NBC series "The Gilded Age" soon.

However, Fellowes could not let go of the project and would not budge to the wishes of ITV.

"ITV wanted Julian to let someone else do it but it wasn't something he wanted," said a "high-level production" source told Radio Times. "Downton is Julian's."

Hugh Bonneville, who plays Lord Grantham on the show, said he did not believe someone could have taken over for Fellowes.

"Julian's writing is distinctive," he said in an earlier interview. "The style and wit and the way he constructs scenes. I only recently realized that you go into a scene with one thing and leave with another. There is a momentum there. A scene starts with something then becomes about something else. When people try and satirize it they never get it quite right because you can't copy Julian."

Although the show may be over, Fellowes has hinted that it could be coming back and also did not turn down the idea of a film.

The Mirror reports that the "Downton Abbey" creator proposed the idea of a spin off show set in the 1970s.

"I think in 10 years it could be quite fun, when we have all forgotten about it, if it came back as Downton struggling in the 1970s. We could have all new different situations," he said when asked at Lord Mayor's Mencap Fashion Show in London.

He also said he had other ideas for spin off shows.

"We could have shows just focusing on Mr. Bates and Anna. It depends on the actors," he added.

Since most landed families continues struggling following the Second World War and the British Empire collapsed, it would be interesting how the family's descendants dealt with issues of the time, including mass strikes, immigration, and advancement of women.

Fellowes, during the interview, did not reject the possibility of a movie, saying: "It is just talk at the moment. But I like the idea of a film as we could take the characters and situations and have a film budget. We could give it some welly...make it fantastically good."

However, he did say the Christmas Special will be two hours instead of the usual hour and a half.