Sources told Us Weekly the 29-year-old American actress and 27-year-old English musician got engaged over the holidays. The couple have been linked since the summer.
Agron appeared to hint at the happy news Jan. 4, tweeting, "Hope everyone had a gorgeous holiday season. Happy 2016! Couldn't be more excited over here." She also shared a photo of herself and Marshall looking into a sunset, writing, "Old friends, new memories. Happy New Year!"
Insiders told the magazine Agron "seemed really happy" with Marshall when the pair attended the "She's Funny That Way" after-party in August. The actress previously dated actor Thomas Cocquerel, while Marshall was linked to singer Katy Perry.
Agron is best known for playing Quinn Fabray on Fox series "Glee," which came to a close after six seasons in March. She is slated for a number of upcoming films, including "Jekyll Island" with AnnaSophia Robb, but told Galore in 2014 she won't pursue music.
"I guess I have to say no to an album in my future," she said. "You never know! It'd be nice to get into stuff that was more me, though I've loved everything I've had the chance to sing on 'Glee.' I'm lucky, really."
Marshall is the banjoist in Mumford & Sons, and last released Wilder Mind with the band in May. The record debuted at No. 1 on the Billboard 200, and includes the singles "Believe" and "The Wolf."
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