The show also marked Underwood's first major appearance since giving birth to her son, Isaiah, earlier this year. As she accepted the Female Video trophy for "Something in the Water," she said her little man has already inspired a lot of new music. Her dynamic performance of "Little Toy Guns" came towards the end of the broadcast.
Lady Antebellum opened the show with their latest single, "Long Stretch of Love," before welcoming pop/EDM star Zedd to the stage for a joint performance of his pop hit, "Beautiful Now." Darius Rucker entertained thousands of fans on Lower Broadway with his hit, "Homegrown Honey," and Reba McEntire made her return to the CMT Music Awards stage for the first time in 10 years to sing "Going Out Like That."
Jason Aldean delivered his sexy current single, "Tonight Looks Good on You," with his wife, Brittany, singing along in the audience. Eric Church performed "Like a Wrecking Ball" in the round with a drummer and organist backing him up as he played electric guitar.
Luke Bryan worked the crowd with "Kick the Dust Up," and Jake Owen showed off some fancy footwork during a highly-choreographed performance of his new song, "Real Life." Zac Brown Band was on hand to sing their #1 hit, "Homegrown," and Keith Urban premiered his brand-new single, "John Cougar, John Deere, John 3:16." Kenny Chesney gave the final outdoor performance of the night, singing his hit, "American Kids."
Sam Hunt recalled attending the CMT Music Awards as a fan as he accepted the Breakthrough Video trophy for "Leave the Night On." He later took selfies with fans in the crowd while performing "House Party." Florida Georgia Line accepted the Duo Video of the Year trophy for "Dirt" and later took over the outdoor stage to debut their new single, "Anything Goes."
In the night's most surreal moment, Arnold Schwarzenegger drove show hosts Erin Andrews and Brittany Snow around Nashville in an Uber-alternative called Guuber. Other Guuber drivers included Steven Tyler, who drove Alan Jackson, and talk show host James Corden, who drove Justin Bieber as they both confessed their love for Luke Bryan and sang the country star's song "Country Girl (Shake It for Me)."
New country stars RaeLynn, A Thousand Horses, Frankie Ballard, Kelsea Ballerini, Chris Janson, and Maddie and Tae all played snippets of their biggest hits throughout the night.
Here's a list of winners for the 2015 CMT Music Awards, held at Bridgestone Arena in Nashville on Wednesday night:
Video of the Year Carrie Underwood, "Something in the Water"
Male Video of the Year Luke Bryan, "Play It Again"
Female Video of the Year Carrie Underwood, "Something in the Water"
Group Video of the Year Lady Antebellum, "Bartender"
Breakthrough Video of the Year Sam Hunt, "Leave the Night On"
Duo Video of the Year Florida Georgia Line, "Dirt"
Collaborative Video of the Year Miranda Lambert with Carrie Underwood, "Somethin' Bad"
CMT Performance of the Year Bob Seger and Jason Aldean, "Turn the Page"