Why was Charlton Heston fourth billed?

The story goes that Heston himself was about to reject the offer to play a supporting character like Steve Leech until Heston's agent reminded him that it was director William Wyler he'd be working with -- Wyler, who was then and even in the decades since his passing considered to be one of the premiere filmmakers in the entire motion picture industry. Little did Heston know how richly he'd be rewarded for settling for "second banana" in THE BIG COUNTRY: Wyler was sufficiently impressed with Heston's work in this picture that he would immediately cast Heston as the star of BEN-HUR.

Okay folks, show's over, nothing to see here!

Ultimately it was a supporting role, but a good one for him.

It was made up to him in Ben-Hur.
He won the Oscar for Best Actor.

I think I read that it was because Peck, Jean Simmons and Carroll Baker were signed first. Hence, Heston got billed behind them. Whenever my local station would air it when I was growing up, they would advertise it along the lines of "Gregory Peck and Charlton Heston in The Big Country" most likely since Heston was better known among the general viewing public by that time than Misses Simmons and Baker.

It was a good role for Charlton Heston and he played it very well. I think he wanted to branch out into high quality films after The Ten Commandments (itself a high quality film), and The Big Country, while it didn't offer him the leading role, did give him a good one. The working with William Wyler factor was surely a deal sweetener for Heston. One thing no one has mentioned on this thread that needs to be cleared up (as I see thing): Heston's role wasn't truly a supporting one.

The Big Country was a big picture, as its title implied, and big pictures are often multi-star efforts, Tony Curtis did the same thing Heston did when he took a lower billed role in Spartacus; and so did William Holden in, first, Born Yesterday, and then The Country Girl. Both films were big hits, wons their lead actresses Oscars; and yet in both pictures Holden got third billing.

I'd call Heston's role more featured, as in co-starring, than truly supporting. Gone With the Wind is one of the best examples of this kind of casting, with three very well know stars, plus a relatively obscure up and comer: Clark Gable was far and above the biggest star name, Vivien Leigh the "unknown factor", since she wasn't well known in the States; Leslie Howard, usually top billed, third billed, was a highly regarded player and a true star with more prestige than Gable, he was insurance that GWTW would be if nothing else classy; and Olivia de Havilland was a quite well known young lady best known at the time as Errol Flynn's frequent co-star over at Warners.