5 Songs You Probably Didn't Realize Were Written by Taylor Swift

When Swift was still dating Scottish DJ Calvin Harris, she cowrote his hit song with Rihanna under the pseudonym Nils Sjöberg. While she initially wanted to keep their collaboration a secret, her team later confirmed her songwriting credit shortly after Swift and Harris split and she started dating Tom Hiddleston. The move led Harris to go on a Twitter rant insinuating that her team was deliberately trying to make him look bad. "Hurtful to me at this point that her and her team would go so far out of their way to try and make ME look bad at this stage though," he wrote in a series of since-deleted tweets. "I figure if you're happy in your new relationship you should focus on that instead of trying to tear your ex bf down for something to do."