In the 1920s and early 1930s, samba was pulsing across Rio’s favelas and working-class neighborhoods, and it could have stayed there but for the magic of radio. Radio was an essential component in the dissemination of Brazil’s emerging national music. It was a vehicle for the popularization of many great sambas by the composers from the Estácio neighborhood, where the first samba school was born. Other important samba composers at the height of the radio era in the 1930s included Noel Rosa, Ary Barroso, Ataulfo Alves, Assis Valente, and Dorival Caymmi. Some of the most popular singers from the period included Mario Reis, Francisco Alves, Chico Alves, Orlando Silva, and Carmen Miranda. The latter became a huge star on Broadway and in Hollywood in the 1940s and ‘50s.

One radio station had the biggest impact on shaping popular tastes throughout the country. It was Rádio Nacional, based in a building in downtown Rio that was South America’s first skyscraper, built in 1927. If you visit the building today, you can kind of tell. The elevators rattle on their way up, and there’s a kind of dusty feeling in the air. The hallways are filled with posters of golden-age stars, flashing fading smiles at visitors as they pass. It’s like a place time forgot, but if you enter one of the wood-paneled studios, you’ll see there are signs of life after all.

In one studio, musicians rehearse for a live broadcast later in the week. The backing band is the Época de Ouro, the legendary choro group founded by Jacob do Bandolim in the 1950s. Choro is a type of instrumental Brazilian music from Rio that predates the modern samba. Época de Ouro had a popular show on Rádio Nacional, and while the personnel has changed a bit, the group still performs regularly on the radio.

It is hard to imagine now, but Rádio Nacional was once the centerpiece of Rio’s glamorous entertainment industry. Radio stars like Marlene, Emilinha Borba, and Cesar de Alencar were massive celebrities. There were radio fan clubs and radio magazines. The glowing heart of the whole system was Rádio Nacional’s 500-seat auditorium. The crowds lined up on Wednesday to buy tickets for Saturday. On Wednesday, Thursday, and Friday, they stayed there sleeping in the streets, waiting to get tickets. Everybody came to Rádio Nacional.

When Rádio Nacional first started in 1936, it wasn’t actually national at all — it only broadcasted in Rio. But by the early 1940s, it was transmitting throughout the country. According to Cristiano Menezes, the current director of the station, it was the first truly national form of mass media in Brazil. Menezes said, “We often say here that Rádio Nacional showed Brazil to the Brazilian. It built or helped to strengthen the idea of the nation. And it absolutely helped to strengthen samba as this thing of national identity.”