After the audition, he engaged the 20-year-old singer for the 1913 Parma Verdi Centenary (which included Oberto, Conte di San Bonifacio[1] and Un ballo in maschera), and also signed her for his Philadelphia-Chicago Opera.

Her first role in Philadelphia was Isabella of Aragon in the United States premiere of Alberto Franchetti's Cristoforo Colombo, followed by Verdi's Aida on 29 November 1913 at the Auditorium Theatre in Chicago.

[4] She added several roles to her stage repertoire with the Chicago-Philadelphia company: Santuzza in Mascagni's Cavalleria rusticana (Dallas), Donna Anna in Mozart's Don Giovanni (Philadelphia), Klytemnestra in Vittorio Gnecchi's Cassandra (Philadelphia—Western Hemisphere premiere), and Elsa in Lohengrin in English (Seattle).

In the spring of 1914 she went to London where she debuted at Covent Garden in Aida with Enrico Caruso, participated as Helen of Troy in Boito's Mefistofele with Claudia Muzio, John McCormack and Adamo Didur, and substituted for Claire Dux as the Countess in Mozart's Le nozze di Figaro.

This led to an engagement at the Teatro Costanzi in Rome for more Francescas, Aidas and two novelties, Fedra, a prize-winning opera premiere by a young Romano Romani (later Rosa Ponselle's coach and mentor) and Abdul by Brazilian Alberto Nepomuceno.

The annals of operatic performances in South America oftentimes read as the "greatest" Italian opera to be seen, the Teatro Colón in Buenos Aires a defining theatre.

Mocchi took Raisa to South America in May 1915 for a long season, first in Buenos Aires and Rosario in Argentina, Montevideo in Uruguay and São Paulo, Rio de Janeiro and Porto Alegre in Brazil.

In addition to her Francescas and Aidas (including another with Caruso) she added Meyerbeer's L'Africana also starring Titta Ruffo, and sang the Marschallin in the South American premiere of Der Rosenkavalier by Richard Strauss in Italian with Gilda dalla Rizza as Octavian and the then unknown Amelita Galli-Curci as Sophie.

In 1916 she reprised her Francescas and Aidas at the Rome Opera and returned to South America for another exhausting season, adding Alfredo Catalani's Loreley, Valentina in Meyerbeer's Gli Ugonotti (Les Huguenots) and Alice Ford in Verdi's Falstaff to her repertoire.

After her return to Chicago in 1916, Raisa, along with Mary Garden, Edith Mason, Claudia Muzio, and Galli-Curci, were the lead sopranos around which the repertoire of the company revolved.

This is significant as Claudia Muzio had performed Norma with some success in Italy and South America, but staked no claim to the role over Raisa in Chicago.

In Chicago she added Maddalena in Andrea Chénier, Zina in Raoul Gunsbourg's Le Vieil Aigle, Isabeau in the North American premiere of Mascagni's opera, Basiliola in Italo Montemezzi's La Nave, Puccini's Suor Angelica, Elisabeth in Wagner's Tannhäuser, Minnie in Puccini's La fanciulla del West, Puccini's Madama Butterfly (at the Ravinia Festival outside Chicago, also Giordano's Fedora at Ravinia), Toinette in Frank Harling's jazz opera A Light from St. Agnes, Rosalinde in an English-language Die Fledermaus by Johann Strauss, and Zandonai's Conchita.

The premiere was on 25 April 1926 with Raisa as Turandot, Miguel Fleta as Calaf, and Maria Zamboni, a Scala lyric soprano as Liu, replacing Mason who was pregnant.

Raisa and Rimini invested their considerable earnings in Insull securities (actually a ponzi scheme) and eventually lost their fortune, on paper estimated in the range of a million dollars.

The Chicago Opera was broadcasting nationally since 1927, every week for one hour; Mary Garden, Claudia Muzio, Frida Leider, Raisa, Tito Schipa, Eva Turner, Alexander Kipnis and Vanni-Marcoux are some of the headliners who were heard on the radio across America.

Since January 1931 when she left the stage to prepare for the birth of her daughter, having had six unsuccessful pregnancies, many things happened: the demise of the Chicago Opera, the world-wide deteriorating economic situation and a general contraction of operatic activity in the United States.

She recorded four verismo arias for La voce del padrone in Milan, and sang five performances of Gli Ugonotti at the Arena in Verona with Giacomo Lauri-Volpi and a stellar cast.

Their careers merged and after retirement in 1938 they opened a voice/opera school together in Chicago, first at the historic Congress Hotel, across from the Auditorium Theatre, and during World War II they moved to North Michigan Avenue.

Lauri-Volpi in his seminal book on singers of his experience and knowledge, Voci Parallele, states that by 1933 Raisa's voice was but an x-ray of how he remembered her earlier in her career.