Game of Thrones season 4 premiere gets biggest HBO ratings since The Sopranos finale

Some 6.6 million viewers tuned in to watch 'Two Swords' on Sunday night

Jack Gleeson as Joffrey Baratheon in Game of Thrones (Home Box Office)

Excitement for the Game of Thrones season four premiere translated into record viewing figures for HBO on Sunday night, debuting with 6.6 million viewers.

The hotly-anticipated premiere "Two Swords" is now the US network’s most-watched episode since 11.9 million tuned in for the 2007 series finale of The Sopranos.

Social media went mad for the start of Game of Thrones ’ fourth run, with 1.9 million Facebook users talking about the show and over 2.8 million interactions related to it.

A replay of the first episode at 11pm, two hours later, added another 1.6 million viewers to bring the total ratings figure to 8.2 million.

Westeros devotees had waited nine months for a new hour of Game of Thrones , which last season opened to 4.4 million viewers.

The fantasy series’ previous peak had been 5.5 million during episode six of that season, “The Climb”.

Police are now cracking down on illegal download websites, after the season three finale became the most-pirated TV episode worldwide, with 5.9 million individuals accessing it via BitTorrent.

Problems with Game of Thrones likely stem from HBO’s refusal to allow the likes of Netflix and Amazon Prime rights to its shows.

Viewers can only watch the series in the US through the TV company’s own Go product, available exclusively to its cable subscriber. In the UK, viewers must pay per episode to watch the show on blinkbox.

Sky Atlantic holds the broadcast rights to Game of Thrones in the UK, but with the exception of the simulcast start of season four, episodes will be aired later on the channel after the US broadcast.

Due to overwhelming demand, HBO’- s Go crashed yesterday, leaving fans with black screens.

"Looks like there's trouble in the realm. Apologies for the inconvenience. We'll be providing updates, so please stay tuned," a statement from the TV company read.