On Sunday night, the return of Game of Thrones scored the show’s best ratings to date — the highest for HBO since the series finale of The Sopranos in 2007. The cable channel has now rewarded Game of Thrones with a renewal for seasons five and six.

Here’s the press release:

HBO RENEWS “GAME OF THRONES” FOR FIFTH AND SIXTH SEASONS

Season Four Debut Scores Highest Viewership Yet

LOS ANGELES, April 8, 2014 – HBO has renewed GAME OF THRONES for a fifth and sixth season, it was announced today by Michael Lombardo, president, HBO Programming.

“GAME OF THRONES is a phenomenon like no other,” noted Lombardo. “David Benioff and D.B. Weiss, along with their talented collaborators, continue to surpass themselves, and we look forward to more of their dazzling storytelling.”

Based on the bestselling fantasy book series by George R.R. Martin, GAME OF THRONES is an epic story of treachery and nobility set on the continent of Westeros, where summers and winters can last years, and only the lust for power is eternal. The Emmy(R)- and Golden Globe-winning series launched its ten-episode fourth season Sunday, April 6 (9:00-10:00 p.m. ET/PT), exclusively on HBO, with other episodes debuting subsequent Sundays at the same time.

Cast regulars for the fourth season of GAME OF THRONES include: Emmy(R) and Golden Globe winner Peter Dinklage, Nikolaj Coster-Waldau, Lena Headey, Emilia Clarke, Charles Dance, Aidan Gillen, Jack Gleeson, Kit Harington, Diana Rigg, Sophie Turner, Maisie Williams, Isaac Hempstead Wright, Alfie Allen, Jerome Flynn, Conleth Hill, John Bradley, Gwendoline Christie, Liam Cunningham, Stephen Dillane, Natalie Dormer, Iain Glen, Kristofer Hivju, Sibel Kekilli, Rose Leslie, Rory McCann, Michael McElhatton, Iwan Rheon and Carice van Houten.

Among the early critical praise for the fourth season, the Los Angeles Times called GAME OF THRONES “the Best Television Show Ever,” adding that “no other series comes close,” and “television just doesn’t get any better than this,” while Newsday hailed the series as “still TV’s best,” awarding the show an A+. The Hollywood Reporter observed, “The consistency of excellence in GAME OF THRONES is truly something to behold,” and the San Francisco Chronicle described it as “great and addictive.”

The season four premiere of GAME OF THRONES on Sunday, April 6 (9:00-10:00 p.m. ET/PT) was watched by an average of 6.6 million viewers, making it HBO’s most-watched program since the finale of “The Sopranos” in 2007 (11.9 million viewers). The premiere improved 52% over last season’s premiere and 23% over last season’s finale. GAME OF THRONES added an additional 1.6 million viewers from the 11:00 p.m. and 1:00 a.m. replays, for a gross audience of 8.2 million viewers for the night. Season three of the series had an average gross audience of 14.4 million viewers per episode.

Season four credits: The executive producers of GAME OF THRONES are David Benioff, D.B. Weiss, Carolyn Strauss, Frank Doelger and Bernadette Caulfield; co-executive producers, Guymon Casady, Vince Gerardis and George R.R. Martin; producers, Chris Newman and Greg Spence.

What do you think? Are you glad to hear that Game of Thrones has been renewed so far in advance? How long do you think it should run?