The Brazilians were given the quick test on Thursday after they claimed to be traveling to Britain for Liverpool's Mathew Street Festival, which celebrates the lives of the northern English city's most famous sons.
Festival organizer Bill Heckle was quoted as saying by the Liverpool Daily Post on Friday that the Brazilians did not know the answers to several questions posed by Portuguese-speaking immigration officials.
They were stumped when asked who Yoko Ono was and erroneously told officials that Ringo Starr had died, according to the report.
A spokeswoman for the Home Office confirmed that six Brazilians were refused entry into Britain on Thursday but declined to give details, citing official policy not to discuss individual cases.
"Anyone trying to enter the country must satisfy officers that they meet immigration rules," she said on customary condition of anonymity. "If they say they are here for a particular event, officers will check this is really the case."
The six were among a group of 72 people on an organized tour from Rio de Janeiro. The rest of the party was allowed through immigration and continued their journey to Liverpool for the festival.
A spokesman for the Cavern Club Brazil, which organized the trip, said the group's treatment had been "ridiculous and very upsetting."
"They played songs and asked us to name them. They actually made people sing Beatles songs," Fabiana Carvalho said. "Some of the young people don't know that much about The Beatles — they are here to see the Brazilian bands, and to travel."