Throughout Captain America's history, he has encountered his fair share of allies and enemies. While the circumstances in which he meets friends and foes don't always coincide, there have been instances where one directly influences the other. One example of this can be found in an early issue of Captain America, where the truth about how Steve Rogers met Sam Wilson is revealed to have a sinister connection to one of Cap's oldest enemies. The revelation rocked the Star-Spangled Avenger to the core and also embued Sam with abilities of his own that he's used even in his recent appearances.
In the past, Sam and Steve met on the island Exile, where the duo worked together to defeat the Red Skull and his henchman. Not long after their team-up, the two decided to work together as partners. However, it is revealed in Captain America and the Falcon #186 (by Steve Englehart, John Warner, Frank Robbins, Mike Esposito, Michelle Wolfman and Dave Hunt) that their coincidental meeting was anything but. In fact, it was Cap's longtime enemy, the Red Skull, that was pulling the strings the entire time. As a result of the Skull's meddling, Sam became nothing more than a deep-seated plan to defeat Rogers when the time was right.
Before the reveal, Sam's origin describes him as a good person who lost both of his parents to gang violence and muggings. To honor them, he became a social worker and traveled the world to help those in need. Eventually, this path placed him on Exile, where he met Steve and fought the Red Skull. However, thanks to the Skull's meddling with the Cosmic Cube, he could fabricate this reality and make Sam believe it to be true. The issue explains that Sam was actually a street hustler named Snap Wilson who traveled to Brazil to do a job for the mob. Thinking he could take the money for himself, he attacked the pilot of their private jet, causing it to crash near Exile.
While there, he meets the Red Skull, who is wearing a disguise and is manipulated into putting on his Falcon outfit to mobilize the native people of the island and fight alongside Steve. According to the Skull, he had changed everything about Sam to fool Steve, but he kept his love of birds. In fact, he even gifted Sam the ability to speak to them, including his pet falcon, Redwing. This deception would remain a part of Sam's history for decades following the reveal. However, thanks to Cap's support, Sam was able to return to being a hero and eventually picked up the mantle of Captain America.
One of the darker factors of Captain America and the Falcon #186 was the treatment of Sam Wilson by the Red Skull. Because he was a Nazi, the Skull never avoided using heavy racial slurs throughout the issue. He demonstrated that his actions were as racially motivated as they were about beating Captain America. The villain's deplorable actions in the issue were later addressed in All-New Captain America #3 (by Rick Remender, Stuart Immonen, Wade Von Grawbadger, Marte Gracia, Dono Sánchez-Almara and Joe Caramagna), where it was revealed that the Red Skull's plan to change Wilson's past was all a racist smear campaign. In reality, Sam really was a social worker who met Steve Rogers on a distant island where he would eventually suit up as his partner.
While Sam's criminal past was scratched from the official Marvel canon, his ability to speak to birds remained. Whether gifted by the Red Skull or not, these powers have remained an invaluable asset to the Falcon's arsenal and he has used them to help prove himself as a hero worthy of wearing the iconic shield of Captain America.