LOS ANGELES – The ancient battle of Thermopylae was the stuff of 2007’s first certified blockbuster as the bloody action tale “300” debuted with ticket sales of $70 million over its opening weekend, according to studio estimates Sunday.

That’s about $233,000 for every one of the legendary 300 Spartan soldiers who fought off a much larger Persian force in the epic battle.

“On a Spartan-by-Spartan basis, that’s a lot of money,” said Paul Dergarabedian, president of box-office tracker Media By Numbers. “Summer came a little early, because this is a summer-style opening.”

The number of movie-goers for the Warner Bros. epic “300” outnumbered crowds for the rest of the top-10 movies combined. If the estimate holds when final numbers are released Monday, “300” would break the record for best March debut ever, topping the $68 million haul for “Ice Age: The Meltdown” last year.

“300” played in 3,103 theaters, about 850 fewer than the “Ice Age” sequel, making its box-office performance even more notable. It averaged $22,567 a theater, a whopping number for a wide release.

The total for “300” includes $3.4 million from 62 IMAX theaters, a record opening weekend for the large-screen format.

Buoyed by “300” and some solid holdovers, Hollywood business soared, with the top 12 movies totaling $139.4 million, up 49 percent from the same weekend last year.

“300” bumped off the previous weekend’s No. 1 movie, Disney’s “Wild Hogs,” which slipped to second place but held up well with $28 million, raising its total to $77.4 million.

In limited release, Fox Searchlight’s immigrant drama “The Namesake” opened strongly with $250,762 in six theaters, averaging $41,794. Centered on an Indian family’s assimilation in America, “The Namesake” expands to more theaters Friday.

Going into the weekend, movie attendance had been lagging 1 percent behind last year because of a slump in January and February. Attendance now is up nearly 2 percent for the year because of the strong weekend, according to Media By Numbers.

“300,” adapted from Frank Miller’s graphic novel, stars Gerard Butler as Leonidas, king of the Greek city-state of Sparta, who leads his vastly outnumbered men against the Persian invaders.

Directed by Zack Snyder (“Dawn of the Dead”), “300” presents the actors against digitally created backgrounds to re-create the look of Miller’s graphic novel, a technique similar to that used on the movie adaptation of Miller’s “Sin City.”

“It’s a new-fashioned version of an epic movie. Great, old-fashioned storytelling with all the brilliant use of the technology available to us now,” “300” producer Mark Canton said Sunday.

Heavy on violence, the movie had an R rating, normally a damper on a film’s blockbuster potential. But “300” wound up with the third-best debut ever for an R-rated movie, behind “The Matrix Reloaded” at $91.8 million and “The Passion of the Christ” at $83.8 million.

“The violence doesn’t bother anybody because it’s done in a way that’s not offensive,” said Dan Fellman, Warner Bros. head of distribution. “People love the movie, they love the originality. The best thing you can have for a film is great word of mouth. When the public is selling the movie for you, that’s when you have a real success.”