“The King’s Speech” enjoyed a regal opening in its home territory this weekend, taking £3.5 million ($5.5 million) to become the highest-grossing pic of the three-day period in Blighty.The Colin Firth-Geoffrey Rush starrer, which played on 395 screens for a $13,851 screen average, provided the biggest-ever opening weekend for distrib Momentum Pictures, the British arm of Canada’s Alliance Films. It beat four other openers: Warners’ “127 Hours,” No. 2 with $3.4 million on 310 screens; Lionsgate’s Russell Crowe starrer “The Next Three Days,” No. 5 with $1.6 million on 425; Paramount’s “Season of the Witch,” which took just $870,427 on 306; and Universal’s “It’s Kind of a Funny Story,” which opened with $127,571 on 100. “The King’s Speech” received 15 bids in the BAFTA longlist unveiled on Friday. The same day, its B.O. hit $1.6 million, a strong opening day figure bolstered by paid previews and Q&As, encouraging for a film marketed toward an older crowd and not the typical Friday night movie. Result is especially encouraging for Momentum, which developed and co-financed the $12 million pic as part of its first-look deal with producers Iain Canning and Emile Sherman’s See-Saw Films.Momentum prexy Xavier Marchand said the U.K. response had been “incredible.” “Momentum has been involved with ‘The King’s Speech’ from early on and this weekend is the culmination of over a year’s hard work and great passion for the film,” he said. The Weinstein Co. released the film in the U.S. on Nov. 26. Stateside cume is $33.3 million after an estimated $6.8 million from 758 locations this past weekend.