Although Pulis has signed a 2 1/2 year-contract, the 56-year-old Welshman's priority is replicating the rescue act he performed so unexpectedly for Crystal Palace last season.
The Premier League manager of the year award was bestowed on Pulis last season for taking Palace from last place when he was hired to an 11th-place finish within six months.
The situation is not as perilous yet for West Brom, which was a point above the relegation zone before Thursday's match at West Ham. But the fear of relegation was troubling enough for the central England club to fire Alan Irvine on Monday after just four months as a Premier League manager.
In Pulis, West Brom is gaining a more far experienced coach, who has been out of work since quitting Palace on the eve of this season. Before focusing on Premier League survival, the former Stoke manager's first game in charge of West Brom is against non-league club Gateshead in the third round of the FA Cup on Saturday.
"Every successful club is built on unity and that is what I shall strive to help bring to Albion," Pulis said "We need everyone together from top to bottom — the supporters, all the staff, the players, everyone who has an interest in the club's welfare. With that, we can go forward together and hopefully take this club up the Premier League."
Pulis' reputation was forged at Stoke, which he took from the second tier to the top flight where an aggressive, long-ball style made the team hard to beat. The tactics did not always impress rivals, and were once disparaged by an official West Brom publication.
"Stoke train with cannons rescued from local medieval ruins," a match report in the West Brom program read in the 2007-08 season. "Footballs are loaded into them and fired into the distance ... it's a game plan that squeezes the life out of what used to be known as football."
But with Pulis becoming West Brom's fourth manager in just over a year, the club is far more appreciative now of his survival specialism.
The West Brom website on Thursday praised Pulis for making his Stoke side "such a thorn in Albion's side throughout a seven-year stint," before highlighting his "proud record of never suffering relegation as a manager."
"He arrives with Premier League survival the priority target outlined by the Albion board," the club website said.
Rob Harris can be followed at www.twitter.com/RobHarris