How is the title of "'Italian' Concerto" derived?

Answer 1

Yr question is vague and I'm not sure to which Concerto Italiano you're referring.
However I've 2 options :
The Italian Concerto (properly entitled Concerto in the Italian Style and this is the reason of its name), BWV 971, is a three-movement solo harpsichord concerto composed by Johann Sebastian Bach in 1735. The work was published as part of Clavier-Übung II, along with the French Overture. The Italian Concerto has become quite popular among Bach's keyboard works, and has been widely recorded both on the harpsichord and the piano.
Its three movements are as follows:
Without tempo indication—usually indicated as
Allegro
Andante
Presto
The Italian Concerto's two lively F major outer movements, in a ritornello style, frame a central arioso-style movement in the relative minor, D minor.

Though a concerto by definition relies upon the contrasting roles of different groups of instruments in an ensemble, Bach achieves a similar effect by creating contrasts using the forte and piano manuals of a two-manual harpsichord alternatively throughout the piece. (Bach also transcribed real Italian concertos by Vivaldi and others (BWV 972-987) for solo harpsichord (and others for solo organ or pedal harpsichord.).



Concerto Italiano is also an Italian early music ensemble well-known for their interpretations of Monteverdi and Vivaldi, among others.
The historically informed performance ensemble was formed by the harpsichordist Rinaldo Alessandrini, and made its Rome debut with Francesco Cavalli's La Calisto in 1984. Since then, Concerto Italiano has recorded Monteverdi madrigals, which have won numerous awards, including the Gramophone Award three times. Other major international awards garnered by this ensemble include Preis der deustschen Schallplattenkritik, Prix de la Nouivelle Academie du disque, Premio internationale del disco Antonio Vivaldi (Cini Foundation), and the Prix de l'Academie Charles Cros.
Concerto Italiano is under exclusive contract with OPUS 111, which is now under the umbrella of the large French label, Naive. Most recently, with conjunction with the National University Library in Turin, Concerto Italiano has been recording all the operas and concertos of Vivaldi, many of which have not been performed for over 300 years. Highlights include Concerto Italiano's recordings of the opera L'Olympiad, La Senna Festeggiante, La Quattro Stagioni (hailed as one of the best versions of the work by Gramophone), a reconstruction of a possible Vespers for the Ascension of the Virgin Mary (Vespri per l'Assunzione), and in 2004, an entire CD devoted to Vivaldi's Concerti per Archi.

Answer 2

who's the composer? for which orchestration is it scored? when was it written?
Otherwise you're asking "what's the name of this american team?" without any of the pertinent information.