TV Ratings: 'Game of Thrones' Premiere Is HBO's Most Watched Since 'Sopranos' Finale

Game of Thrones S4EP1 Still - H 2014

Game of Thrones S4EP1 Still - H 2014

Game of Thrones continues to gain momentum. HBO's most watched series returned for its fourth season on Sunday night, breaking its previous viewership record in the process.

The premiere garnered 6.6 million viewers during its 9 p.m. broadcast. That's up 2.2 from last year's then-record 4.4 million premiere -- and up 900,000 from the latest record, 5.5 million, achieved in week six of the third season. The episode now ranks as HBO's most watched telecast since the 2007 series finale of The Sopranos.

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An encore helped Game of Thrones surge even more. 1.6 million viewers tuned in to the 11 p.m. replay for a nightly gross of 8.2 million.

Last year saw Game of Thrones eclipse True Blood as HBO's biggest series, grossing an average 14.4 million viewers every week thanks to live plays, encores, On Demand and HBO Go views. Speaking of HBO Go, the streaming service crashed for the second time in a month on Sunday night. Interest in Game of Thrones, like the True Detective finale, saw usage surge and temporary crashes on many platforms.

Game of Thrones' latest increase can be at least partially chalked up to the series' success with binge watchers. Game of Thrones' first three seasons are available on HBO Go, and the drama also holds the title of TV's most pirated series. Last season's episodes notched as many as 5.9 million downloads according to BitTorrent.

HBO used the expected ratings haul to its advantage, premiering the similarly geek-friendly Silicon Valley at 10 p.m. The comedy proved huge for the network, its biggest half-hour launch since Hung (2.8 million in 2009), with 2 million viewers.

The third-season premiere of Veep followed at 10:30 p.m., averaging nearly 1 million viewers, on par with its latest finale.