"Keep Us Together," a ballad from Jessie J's 2014 album Sweet Talker, nicely encapsulates everything that's embarrassing and gauche about love songs. Over surging pop-glop backing, Jessie's powerhouse voice breathily utters trite emotional banalities. "Ain't easy tryin to stay in love," she coos. "Are we gonna walk out, when it rains?/Just tell me we got enough of love to keep us together." It's gooey, overdetermined, prepackaged, meaningless schmaltz, and I kind of adore it.

Nor am I alone. As Ted Gioia demonstrates in his exhaustive new book Love Songs: A Hidden History, humans of every period and culture have relished listening to, and performing, compositions about love. Scholars have found references to women composing songs for their sexual organs in relics from ancient Sumeria. In China, Confucius compiled songs with lyrics like, "A very handsome gentleman/Waited for me in the lane/I am sorry I did not go with him." Troubadours have sung supposedly chaste tunes in praise of married women; folk songs have told stories of adultery, incest, and death. But one way or another, love, and its close attendant, sex, have long been a musical preoccupation.

The prevalence of love songs isn't exactly a surprise. What's interesting, though, is that my ambivalent reaction to "Keep Us Together" has a similarly long history. Love songs, over the centuries, have almost always provoked embarrassment and critical disdain, not to mention authoritarian censure. Confucius' collection of songs, the Shijing, was banned at various points in China; merely discussing it could be grounds for execution. Even during periods when Confucius' prestige won the work official sanction, the love songs weren't exactly embraced. Instead, they were reinterpreted. "If along the highroad/I caught hold of your hand/Do not be angry with me/Love takes time to overcome" was read as a lyric devoted to "thinking of one's noble lord"—meaning, as Gioia says, that "not just the erotic elements, but even the romantic couple disappear in the hermeneutical fog."

This tactic has long been used when it comes to the interpretation of the Old Testament's Song of Songs as well. Whether by outright censorship, reinterpretation, or (as with the adoption of euphemistic metaphors and styles by St. Francis and the poet Rumi) co-optation, religious and civil authorities worked to contain, marginalize, or bury erotic or romantic elements in music. As Gioia says, "The history of the love song is also the history of the repression of the love song."

Because love songs were considered dangerous and marginal, creators and singers of love songs have consistently come from marginal groups. In particular, Gioia says, women have often been the originators of love song traditions, which have then been codified and transmitted by men. Sappho is now thought of as a poet, but she was in fact a "singer-songwriter" whose work was accompanied by a lyre. Most of Sappho's lyrics have been lost, which Gioia suggests may have been in part a result of intentional erasure by those uncomfortable with her portrayal of personal emotion. Among with many other examples, Gioia points also to the Medieval Islamic zajal, in which men often took the voice, or lyrical position of women—a quirk that the author connects to textual evidence of a pre-existing, largely unrecorded tradition of women singers.

Love songs were linked to other marginalized groups as well. Singing and music-making has long been a part of the job for many prostitutes and sex workers: The English folk song "Greensleeves" is supposed to have "gained popularity as a melody used to solicit clients," Gioia writes, "and the title possibly alludes to the grass stains on the attire of women who had sex with customers outdoors." Slaves (female and male) have also been great singers of love songs, whether in ancient Roman times, in medieval Egypt, or in the American South. Gioia goes so far as to suggest that the courtly love tradition of the lover enslaved, or subservient, to his feelings of affection has its roots in the association of love songs with servitude. "[L]overs humbly serve the beloved in our romantic music because the originators of these kinds of song were literally slaves and servants."

Gioia's rushed discussion of contemporary music is unfortunately the weakest part of his book. But nonetheless, his historical revelations serve to undermine, or call into question, many of the ways we might think about Jessie J, or current popular music in general. As Gioia notes, critics tend to denigrate love songs in favor of more serious subjects; it's not an accident that critical juggernauts like The Beatles (later in the band's career) or Bob Dylan were associated primarily with other topics. Sexualized performances in videos by Madonna, or Nicki Minaj, or Jessie J are seen as a distraction from serious music—a mass-market concession to prurient interests antithetical to real talent. And, of course, in diverse genres and diverse ways, women have historically been considered secondary, or less authentic than men, whether it's the Robert Johnsons eclipsing the Ma Raineys in classic blues (even Gioia seems to fall for this one), or the way that male hip-hop artists like Kanye West are seen as geniuses while female R&B performers like Beyoncé aren't.

But Gioia's work upends all of those assumptions. Love songs have always been serious—so much so that their emphasis on inner life and personal fulfillment has been seen as a threat to state authority for centuries. Similarly, sexual performance, simulated and actual, has been part of the love song tradition for a very long time. And it's women who have been the true, authentic performers in the love song tradition, and men who have been the borrowers and copiers. Jessie J's big, gloppy emotional love song "deserves respect," Gioia suggests, as an example of "the toughest and most battle-hardened mode of artistic expression." Songs like this one have embarrassed kings, popes, emperors, and critics, but still they keep getting made. "Ain't easy tryin' to stay in love" indeed—but Gioia's book, perhaps, makes it a little easier.