In the Star Wars franchise, it's rare that a ship gets an origin story. But a certain exception was made for perhaps the most famous starship in the galaxy far, far away, the Millennium Falcon, which underwent extensive damage in Solo: A Star Wars Story to become the classic ship fans know and love. But even then, it was still unclear how this particular line of Corellian ships was created. Simply put, the most recognizable ships in Star Wars lore are already flying in large numbers when they are first introduced, from the A-Wings to the TIE Fighters.
However, in Star Wars: Rebels, fans learned how one of the most distinct ships in the Rebellion was created. In fact, the Season 2 episode "Wings of the Master" revealed how the B-Wing came to be, and how it would become an important addition to the Rebel fleet.
When fans first meet the Rebellion in Star Wars: Rebels, it is still in its infancy. The bulk of the freedom fighters consists of the Phoenix Squadron, a small fleet made up of several large starships, the Ghost and a handful of A-Wing fighters. In "Wings of the Master," the fleet travels to the planet Ibaar where the people on the planet are in need of supplies. However, when the Rebels get there, they find that the Empire has set up a blockade led by Agent Kallus.
As an expert pilot, Hera leads the charge but the attack on the Empire blockade leads to catastrophic losses and worse still, the Rebels are forced to retreat. With the people of Ibaar still in desperate need of supplies, the Rebellion leaders try to devise a plan that would allow them to get past the blockade without more losses, but there is nothing currently in their fleet or arsenal powerful enough to give them that chance. That is until old Clone trooper Captain Rex mentions an inventor named Quarrie who lives on the planet Shantipole. Quarrie may not be a Rebel exactly, but he's certainly not on the side of the Empire and, better yet, he's been developing a new type of ship -- one that could theoretically get past a blockade.
Hera, Zeb and Sabine then travel to Shantipole in order to see if this ship could help them in the war against the Empire. When they meet Quarrie, the engineer then introduces them to the prototype Blade-Wing, aka B-Wing. The ship's design makes it a difficult target to hit, it's fast and packs a heavy punch. It takes a bit of convincing, but Quarrie eventually gives the prototype to Hera, who flies it into battle against the imperial blockade surrounding Ibaar. And with it, she is able to blast past the Empire, and get the supplies down to the people of the planet. As the episode comes to a close, Quarrie officially joins the Rebel cause and agrees to mass-produce the B-Wings with a few modifications.
After the events of this episode, the B-Wings would then become part of the Rebel fleet and take part in important battles such as Return of the Jedi's attack on the second Death Star. With the creation of this new ship, the Rebels were able to help people on Ibaar and, with this simple act, it proved to be an important addition to the Rebel fleet. Without the B-Wings, the Rebel cause might have failed altogether.