This mini-epic is the personal favorite Lungs track of Florence Welch the frontwoman of Florence + the Machine. She told The Sunday Times September 20, 2009 that she created it with her keyboard player, Isabella Summers, "in about half an hour with the worst hangover ever."
Welch told The Sunday Times that it's a song about how being in love means "you give yourself up to the dark, to being blind."
On this song Welch is backed by a piano, drums and a harp played by her harpist, Tom Monger.
The album's co-producer Paul Epworth, whose résumé also include Welch's old school chum, Jack Peñate, described this to The Sunday Times, as, "a beautiful piece of music anyway, but that vocal performance was otherworldly." He added: "She reduced me and the other staff to tears. Her voice is almost like a field holler, and combined with the tenderness of the lyrics, it's lethal."
Paul Epworth recalled to Q magazine May 2010 of the first time he met Welch: "To be honest, I thought, 'Won't someone just nail her down?' She was going at two million mph, saying she wanted to make a tribal pagan pop record the whole time. But she's got a flair for invention that's rare. When she recorded Cosmic Love the words came when she was lying on the floor. Then she sang it and everyone in the studio was just crying. She's a great British eccentric, no doubt about it."
This is mentioned in Marisha Pessl's 2014 mystery novel Night Film. A piano store manager explains: "Concert pianists get to be quite chummy with dead composers. They can't help it. Classical music isn't just music. It's a personal diary. An uncensored confession in the dead of night. A baring of the soul. Take a modern example. Florence and the Machine? In the song 'Cosmic Love,' she catalogs the way in which the world has gone dark, distorting her, when she, a rather intense young woman, was left bereft by a love affair. 'The stars, the moon, they have all been blown out.'"
This was featured on several TV shows, including Grey's Anatomy (episode: "Blink"), Gossip Girl (episode: "Panic Roomate"), and Nikita (episode: "Covenant"). The song also played during Aidan's emotional final scene in the May 7, 2018 episode of Coronation Street as he danced with Eva in their last moments together.