In 2004, two different Italian studios imported similarly themed fantasy-adventure series to the US.
W.I.T.C.H. landed at ABC & ABC Family, but because it didn't meet FCC E/I guidelines, it aired at 12 noon (ET) on ABC, where, had it been able to be renewed the following season, would've been subjected to frequent pre-emptions for sports. As it was, the series lasted just the 1 year here in the US.
The Winx Club bowed on Fox, imported by 4Kids for the network's Saturday block, and was in and out of the lineup for 4 years (2004-8) before being cancelled. However, the series remained in production, and returned to US screens 2 years later, when Nickelodeon acquired the show.
Today, the series has been consigned to Nick, Jr., at last check, if not also Nicktoons, but with Christmas a week away, you'd think they'd at least air this episode, "A Magix Christmas", first shown in 2012.
The cast during the Nick era includes Nick alum Larisa Oleynik (ex-The Secret World of Alex Mack) and actress-singer Ariana Grande, the latter being reason alone to have this episode run on Nick over the next week.