Carvalhal was sacked by second-tier Sheffield Wednesday on Christmas Eve, but Swansea surprisingly chose the Portuguese coach to replace Paul Clement, who lost his job on December 20 with the club languishing at the bottom of the Premier League.
The Welsh club said Carvalhal’s contract included the option of an extension at the end of the season.
Carvalhal, who is Swansea’s fifth permanent manager in two years, said difficult challenges such as the one facing his new club attracted him.
“I spoke to the chairman (Huw Jenkins) and a difficult challenge is something I appreciate,” the 52-year-old Portuguese said.
“Everybody understands Swansea is in a very difficult situation and a lot of people would say we need a miracle to stay in the Premier League.
“But I don’t agree because miracles is not something from our world — our job is to win. This job is a very good challenge and we will fight to put the team in a better position.”
To convince Swansea to keep him beyond this season, Carvalhal — who joins compatriots Jose Mourinho at Manchester United and Watford’s Marco Silva in managing a Premier League club — might have to save his new club from relegation.
They sit five points from safety and bottom of the table, without a win in their last four matches after a 5-0 thrashing at Liverpool on Tuesday.
He led Sheffield Wednesday to the Championship play-offs in the last two seasons, but lost his job after an eight-game winless run left them well outside the top six.
Swansea chairman Huw Jenkins is confident Carvalhal can rescue Swansea.
“Carlos’ time at Sheffield Wednesday, which included securing two consecutive play-off places, highlighted that he has great character and personality to lead the squad and the football club, which is vital at such a crucial time,” Jenkins said.
“He is driven and ambitious and, while he has a big challenge ahead of him, I know he will tackle it without fear.”
Leon Britton had been working as a player-caretaker manager, but Carvalhal hasn’t announced if the long-serving Swansea midfielder will stay on the coaching staff.
Would you like to place a soccer bet? Click here to get started in 3 easy steps.