the second world war popularized american jazz not only in europe, but in most other places where american forces were stationed - this expansion continued well into the 50's decade, and on each stop, jazz gained an ever growing cult following.

such was the case in brazil, where young music enthusiasts as well as artists in the neighborhood of copacabana, rio, would gather for samba jam sessions - as improvisation is a key feature of a jam session, participants would often contribute with new sounds and rhythms that they heard during the day. 

given the tendencies of the day,  jazz soon started being incorporated in copacabana's samba jam sessions, often taking place at the beach or in nara leão's apartment, a singer later named 'the muse of bossa nova'.