Nannini's breakthrough came with 1979's California, recorded with the help of Premiata Forneria Marconi. It was an album that effectively announced her transformation into a rock artist, a direction only hinted at in the few tracks of her second LP. Boasting a superb collection of songs, including her first hit single, "America," and controversial cover art depicting the Statue of Liberty holding up not a torch but a vibrator painted with the colors of the U.S. flag, California also opened doors for Nannini in Europe, reaching the top of the charts in Germany, a country where she developed an ardent fan base. She went on to become one of the biggest pop icons in Italy in the '80s, releasing a string of highly successful albums and memorable singles.
Her essential trilogy of albums, including Latin Lover, Puzzle, and Profumo, was produced by Conny Plank (of Eurythmics, Devo, Kraftwerk, and Ultravox credentials), who played a key role in designing Nannini's '80s sound. "Fotoromanza," from 1984's Puzzle, was her biggest hit of the decade, and definitely established her as a major commercial act, not only in Italy but in many parts of Europe as well. Its video, directed by legendary filmmaker Michelangelo Antonioni, became a staple of the blossoming MTV phenomenon in Europe. Other singles from the period include "Ragazzo dell'Europa," "Bello e Impossibile," and "Profumo," all of which were included in her first greatest-hits collection, Maschi e Altri, which sold over a million copies after its release in 1987. At the same time she was busy becoming a pop star, Nannini furthered her independent streak by creating her own record label, Gienne, with manager Peter Zumsteg, and developed her other artistic interests by composing soundtracks, appearing in a Gabriele Salvatores' film, and performing the songs of Kurt Weill and Bertold Brecht with Sting and Jack Bruce at the Hamburg's Schaispielhaus. Nannini's international profile reached a peak in June 1990 when she sang "Un'estate Italiana" with Edoardo Bennato, the official theme song of the Soccer World Cup held in Italy that summer, fondly remembered by soccer fans worldwide as arguably the best World Cup song in history. Subsequently, Bennato and Nannini donated all royalties to Amnesty International.
Nannini wisely chose not to remain stuck in her '80s persona, however, and opted to progressively revamp her sound during the '90s and 2000s, making some of her finest and certainly most ambitious work in the process. Her choice of collaborators reflected her creative restlessness, as her new albums were trusted to producers such as Alan Moulder (Smashing Pumpkins, Nine Inch Nails), Dave Allen (the Cure), and Will Malone (the Verve, Depeche Mode, the Who, Dido, Massive Attack), and featured guests or co-writers such as Jovanotti, Francesco de Gregori, and Dave Stewart. Moreover, years seemed to have added a rougher edge to Nannini’s voice that only highlights the sensuality, irony, and dejection of her characteristically passionate singing modeled after Janis Joplin -- arguably her main influence. Nannini’s later albums aptly combined striking sonic aggression and elements of electronica with string arrangements and traditional Italian lyricism, a method she mockingly dubbed "Heavy Puccini." Her studio output was remarkably consistent, even when she occasionally embarked on more adventurous projects such Pia Come la Canto I, a rock opera based on a minor female character from Dante's Divine Comedy, or Perle, an exquisite acoustic revision of her classics. She also composed the music for renowned animation director Enzo d'Alò’s Momo Alla Conquista del Tempo, presented at the 2001 Venice Film Festival. All the while, Nannini remained a strong seller, thanks in large part to the strength of formidable singles such as "Meravigliosa Creatura" and "Sei Nell'Anima." The latter was also featured in the soundtrack of the blockbuster comedy #Manuale d'Amore, and helped turn Nannini's 2006 album, Grazie, into her greatest success in 15 years. Following in the steps of Maschi e Altri, she released a new compilation roughly every ten years (Bomboloni in 1998, Giannabest in 2007), which invariably reached the top of the charts.
Nannini's original studio recordings continued to perform well during the 2010s. Io e Te reached number one upon release in 2011, Inno did the same two years later (despite selling slightly fewer copies), and HITALIA completed the trifecta in 2014. The latter was an especially ambitious project, representing Nannini's attempt to tell the history of Italian music during the 20th century across 17 specially selected songs. In 2017, she released Amore Gigante, a celebration of love and diversity.
Aside from her music career, Nannini has concurrently developed her literary and social interests. In 1995, she earned a Summa Cum Laude degree in Philosophy from the University of Siena, with a graduate thesis on the subject of the relationship between the human body and the voice. In 2005, she published her first book, the autobiographical Io, and a book of interviews by writer Edoardo Nesi, Rovi