EntertainmentNun who battled Katy Perry over L.A. convent purchase: Pop star has 'blood on her hands'

It's hard to believe it's been a decade since Katy Perry burst onto the scene singing about kissing girls and cherry Chapstick! In honor of the 10th anniversary of her album "One of the Boys," which was released on June 17, 2008, we're taking a look back at her career highlights. Keep reading to relive Katy's biggest professional moments!

Katy Perry started out as a gospel music singer! But after spending two years with Columbia Records and releasing the self-titled album "Katy Hudson" (her real name), she ultimately moved on to Capitol Records. It was there that her career truly took off when she pivoted from religious music to pop and released her second studio album, "One of the Boys," on June 17, 2008. The first single, "I Kissed a Girl," became her very first No. 1 single on the Billboard Hot 100... but it certainly wouldn't be her last!

November 2008 saw Katy Perry win one of her first big awards -- an MTV Europe Music Award. She took home the prize for best new act, but she wasn't just sitting in the audience that night! She actually hosted the ceremony that year and sported this hilarious androgynous look.

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Katy Perry went out on the road for her first headlining tour in January 2009 -- the Hello Katy tour! The concert trek started in Seattle and traversed North America, Australia and Asia before ending in Europe in Austria that November.

Another summer anthem! The first single off of Katy Perry's sophomore album, "Teenage Dream," was a song with Snoop Dogg called "California Gurls," which became Katy's second big summer hit two years after "I Kissed a Girl." The tune played everywhere following its May release and spent six weeks atop the Billboard Hot 100 chart. It even earned a spot on Billboard's "30 Summer Songs of All Time" list!

Songs for a good cause! Katy Perry's October 2010 hit "Firework," also off her "Teenage Dream" album, was the tune of the It Gets Better campaign -- a movement that works to combat harassment against those in the LGBTQ community -- that year. The single's video also enjoyed major success on YouTube (it has more than 1.1 billion views on the site!). The video also took home video of the year honors at the 2011 MTV VMAs.

Katy Perry launched her very first perfume in November 2010! Its name, Purr, served as a nod to her fans, who call themselves Katycats. The bottle was aptly shaped like a kitten.

She's come a long way! 2011 saw Katy's biggest tour yet, the California Dreams tour, which came complete with insane candy-themed costumes and theatrically dressed dancers. It sent Katy all around the world, beginning in Portugal in February 2011 and ending in the Philippines in January 2012. While on the road, Katy grossed $59.9 million worldwide, making the California Dreams tour the 13th biggest concert trek that year, according to Billboard's Top 25 Tours list.

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Katy Perry on the big screen... sort of! In July 2011, Katy lent her voice to "The Smurfs," her first big movie role since making a cameo in "Get Him to the Greek." The pop star voiced Smurfette and was part of the film's massive success -- it made over $563 million at the worldwide box office.

Following in Michael Jackson's footsteps! Katy Perry's "Teenage Dream" spawned not one, not two, not even three No. 1 hits -- it produced five of them! The feat had only been accomplished by one other artist, Michael Jackson, which not only put Katy in good company but made her the first female artist to reach the milestone. It was the song "Last Friday Night (T.G.I.F.)" that clenched that impressive title for the superstar in August 2011.

Katy Perry further expanded her brand with the release of her second perfume, Meow! The fragrance came out in December 2011 on the heels of the success of her first perfume, Purr. This scent also came in a cat-shaped bottle, just in a lighter hue.

January 2012 saw Katy Perry break another record when she became the first artist ever to have four songs sell more than 5 million digital units. She followed up that exciting feat with a pre-Super Bowl performance in Indianapolis ahead of Super Bowl XLVI where she donned a football-themed outfit that embraced both teams competing that year, the Giants and the Patriots.

Katy Perry shared even more of her life with her Katycats in the July 2012 flick "Katy Perry: Part of Me." The 3D concert documentary showed glimpses of Katy's backstory, including her gospel-music roots, while following her path to her mega-successful California Dreams tour. It included some heavy moments, like her split from husband Russell Brand, and some happy ones, such as a few adorable moments with her grandma.

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Woman of the year! Billboard bestowed Katy Perry with its Woman of the Year Award in November 2012 in light of the star wrapping up her huge California Dreams tour, releasing her first film and breaking records on the music charts.

Mixing business with pleasure! Katy Perry and then-boyfriend John Mayer released a duet entitled "Who You Love" in August 2013. The song was featured on John's album "Paradise Valley." This marked Katy's third-ever collaboration. She hadn't lent her voice to another artist's song since Timbaland's 2010 track "If We Ever Meet Again."

Smurfette is back! Katy Perry reprised the role of Smurfette for "The Smurfs 2," which was released in July 2013. Though this flick didn't perform as well as the first, it marked Katy's second foray into voicework.

Another fragrance! Katy Perry released her third scent, Killer Queen, in August 2013. It was her first scent that wasn't cat-themed. Instead, it came in a red ruby-shaped bottle. This scent, which was named after the famous Queen song, went on to win the Consumers' Choice Award at the Canadian Fragrance Awards the following year.

Katy Perry's fourth album, "Prism," was released in October 2013 to rave reviews and a No. 1 debut on the Billboard 200. It had already spawned two successful singles, "Roar" and "Unconditionally," before its release, but third single "Dark Horse" was one of the album's biggest hits, becoming the ninth No. 1 single of Katy's career.

Twitter superstar! In February 2014, Katy Perry set a Twitter record when she surpassed 50 million followers and became the social media platform's most followed user ever.

Katy Perry hit the road once more in May 2014, this time for her Prismatic world tour, which was her most impressive concert trek yet! It kicked off in Belfast, Northern Ireland, and ran for over a year. It featured even more elaborate costumes than those on her California Dreams tour as well as a segment where Katy flew over the crowd carried by fake balloons. The tour eventually ended in October 2015 in Costa Rica, at which point it had grossed more than $204 million worldwide -- making it Katy's most successful tour ever.

In mid-2014, Katy Perry's music video for "Dark Horse" became the most watched video of the year with more than 500 million views on YouTube. By June 2015, it exceeded 1 billion views, making her the first female artist to reach that mark on the platform.

Girl boss! Katy Perry founded her own record label, originally called Metamorphosis Music, in June 2014. The label, a subsidiary of Capitol Records, signed artist Ferras (seen here). His first album included a duet with Katy called "Legends Never Die." In 2016, Katy changed the label's name to Unsub Records.

Katy Perry started off 2015 with a bang -- as the most watched and highest rated Super Bowl performer of all time! And for good reason too. Not only did she ride in on a huge metallic lion, but she went through four outfit changes and featured sharks as backup dancers -- a move that launched a thousand memes! Her Super Bowl XLIX performance even garnered more views than the actual game, with Katy's show drawing 118.5 million viewers compared to the Super Bowl's 114.4 million.

Instead of delivering another deep dive into her personal life, the pop star opted to do a straight concert film for her second movie, "Katy Perry: The Prismatic World Tour." The Epix production premiered in March 2015 and gave fans a close-up view of the elaborate and impressive stage show... without the front-row seat price tag.

Katy Perry's "Roar" single was a huge hit, but its music video was just as popular! In July 2015, the video surpassed a billion views on Vevo, making her the first artist to ever have two videos surpass a billion views.

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Making money! 2015 saw Katy Perry ranked at No. 1 on Forbes "Top-Earning Women in Music" list. She also topped the "World's Highest Paid Musicians" list after she reportedly raked in $135 million that year.

From the Super Bowl to the Olympics! Katy Perry delved back into the world of sports in 2016, following up her major Super Bowl performance by recording the anthem for the 2016 Olympics! Her song, "Rise," was released as a standalone track and was meant to inspire the athletes competing.

Early 2017 saw Katy Perry debuting a new look along with some new music! The star cut off her signature long locks and dyed her hair platinum blonde before promoting new tracks including "Chained to the Rhythm" featuring Skip Marley, the first single off her summer album "Witness." Katy's next two singles also featured collaborations with big artists: Migos was on "Bon Appetit" and Nicki Minaj was on "Swish Swish."

All of those collaborations were featured on "Witness," Katy Perry's fourth studio album. The album dropped in June 2017 and despite garnering mixed reviews, it still topped the charts. To promote the effort, Katy tried something new -- a livestream! The pop star broadcast herself on a YouTube livestream dubbed "Katy Perry Live: Witness World Wide" for four days in a row, culminating in a live concert.

Another Twitter record! In June 2017, Katy Perry became the first person to ever break 100 million followers on the social media site. That same month, Time magazine aptly put her on its list of "The 25 Most Influential People on the Internet" thanks to that Twitter milestone and her headline-making YouTube livestream.

That same month, June 2017, saw Katy Perry make history once more when her third song received an RIAA Diamond Song Award. That honor is only given out when an artist's song passes the 10 million threshold for song sales and streams, and Katy's tunes "Roar," "Dark Horse" and "Firework" all reached the mark, making her the first artist in history to earn three of these, as only 14 songs had even earned diamond status up until that point.

Leader of the pack! Katy Perry hosted the 2017 MTV Video Music Awards in August that year, and she pulled double duty! Aside from emceeing the show and doing elaborate stunts like descending from the sky dressed as an astronaut, she also performed her song "Swish Swish" alongside Nicki Minaj.

Time to tour again! Katy Perry started her fourth headlining concert trek, Witness: The Tour, in September 2017 in Montreal. The tour's final stop is slated for New Zealand in August 2018.

A new role! Katy Perry signed on as a judge on ABC's "American Idol" revival in late 2017 alongside fellow judges Lionel Richie and Luke Bryan. She reportedly earned $25 million to work on the series, which premiered in March 2018.