Bournemouth manager Eddie Howe has vowed to give his promotion heroes the chance to shine in the Premier League.
Wolves boss Kenny Jackett fears he will lose key winger Bakary Sako after his side missed out on a place in the play-offs.
The 36-year-old Argentinian was a free agent after leaving Inter at the end of last season and, after rejecting an offer from Serie A club Sampdoria, he has opted to join the reigning Swiss champions.
Basle president Bernhard Heusler told the club's official website: "In Walter Samuel Basle have signed a very experienced player with a great personality to boot.
"Once again, this is a transfer that proves how attractive Basle and the Swiss league are becoming."
Samuel, who made 172 league appearances over his nine years with Inter, added: "I am very happy and looking forward to the new challenge and adventure offered by Basle."
The new Swiss Super League season is already under way, with Basle clinching a 2-1 victory in Saturday's opening-day trip to Aarau.