It looks like American television just found its newest fad. Downton Abbey, the British WWI-era drama aired on PBS, has just dominated TV ratings according to Reuters. The show's second season, which premiered on Jan. 8, beat out television big shots Mad Men and Kim Kardashian, ranking with 4.2 million U.S. viewers.

But there's an ironic twist to the drama's success--the early-1900s-based show is drawing just as much attention on social media platforms as it is on television.

There has been a tremendous online response, Sarah Ball, deputy editor of VanityFair.com told Reuters.  PBS does historically have an older audience...but 'Masterpiece' has courted that online fan base. They organized the live tweeting, put up slideshows and extras that really appeal to fans.

The online trend began when the network invited users to a Twitter event to launch the show's second season.

Watching Downton Abbey on MASTERPIECE is more than great television, it's an event, and we're taking it to Twitter! the promotional page read.

Users and viewers were encouraged to mark their posts with the hashtag #DowntonPBS. During the national broadcast of each new episode users can interact with PBS insiders, taking the traditional meet and greet promotional technique to the digital realm.

And the Internet trend seemed to stick, with tweeters posting about the show even a month after the season debut.

There are now three people in my Twitter feed talking about watching Downton Abbey. Guess I have to start watching it now, read one tweet.

I really did not want to like Downton Abbey but dammit it's too good! read another.

Ball said recognized the irony in the online obsession.

It is interesting that a show set in 1917 happens to have such a rabid online fan base, she said to Reuters.

The show, which spawned an 18 percent rise from first season ratings, contributed to its buzz-worthy profile when PBS announced the addition of Shirley MacLaine to its cast last week.

Downton Abbey airs on PBS on Sunday evenings, click here to check local listings.