Prior to his days as Star Fox's ace pilot, Falco Lombardi was originally a member of a space gang known as "FREE AS A BIRD". Katt Monroe was part of this gang as well. In a 2011 Nintendo Dream interview, Takaya Imamura revealed that when Fox was forming his new Star Fox team in the wake of James' death, he heard stories about how good a pilot Falco was as apart of FREE AS A BIRD, and visited him multiple times to try to convince him to join his new team, as he wanted to have an experienced partner due to still being unsure of himself as a leader.

Though originally mentioned in the background lore for the Japanese version of Star Fox 64, FREE AS A BIRD in its entirety would physically appear in "Farewell Beloved Falco", a canonical manga interquel set between Star Fox 64 and Star Fox Adventures that was never localized outside of Japan.

According to the official Japanese guidebooks for both Star Fox 64 and Star Fox Command, Meteo (or "Asteroid Belt" as it's referred to in Command) is said to represent remnants of a destroyed fifth planet from the early days of the Lylat System, which aligns with its close proximity to Corneria, the fourth planet of the Lylat System. It is said that many of the asteroids there contain highly pure metals, and their outer edges have been the site of high-quality mineral deposits, though ultimately what lies in the deepest parts of the asteroids remains unknown.

This information would also appear on the official western Star Fox 64 website and also in the Star Fox 64 Official Player's Guide, though strangely enough, the latter states that Meteo is believed to be the remnants of a ninth planet from the early days of Lylat.

According to the official Japanese Star Fox 64 guidebook, Area 6 was originally a space farm or plantation before Andross' army invaded and turned it into a military base for their forces.

At the beginning of Star Fox: Assault, Andrew Oikonny's rebellion is seen to be utilizing three models of humanoid mechas, which, going by the official Japanese guidebook for Star Fox: Assault, seem to be known as サルデス (Sarudesu). This can be transliterated as "Sardes".

• サルデス MK III S (this seems to be a prototype, judging by Fox's comments. It later appears infected by the Aparoids.)
• サルデス MK III DB
• サルデス MK III DG

These are actually meant to represent evolved forms of the Shogun Warriors featured near the end of Star Fox 64's Sector Y stage, who too in the Japanese version of SF64 are referred to as サルデス (Sarudesu). What is called the Shogun Lord in the English version of the game is also called サルデスII (Sarudesu II) in the Japanese version.

As サル (Saru) is the Japanese word for monkey, and デス (Desu) means death, the literal translation of the name in English should be "Monkey Death".

One of the more enigmatic characters in Star Fox 64 is the tanuki or raccoon dog that only appears in its training mode. On the official Japanese Star Fox 64 website, Slippy reveals that his name is ヤル・デ・ポン (Yaru De Pon), and that he is the president of Space Dynamics, the manufacturers of the Arwing and other vehicles the Star Fox team utilizes in their missions.

His surname seems to reference the du Pont family (ポン spells both "Pon" and "Pont"), a wealthy American family who made their fortune selling gunpowder, and later chemicals and motor vehicles. A popular rumor is that Henry A. du Pont secretly sold gunpowder to the Confederacy during the Civil War; fittingly enough, Slippy implies that Yaru de Pon is involved in "shady weapon deals", suggesting that he might be supplying Andross' forces as well.

Yaru de Pon is also notably the only character in the original Star Fox 64 to not have any voice acting. This was addressed in its 3DS remake, Star Fox 64 3D, where he is now properly voiced by Jay Ward (who also voices Wolf O'Donnell in Super Smash Bros. Brawl and Super Smash Bros. Ultimate, as well as the Nintendo Switch version of Starlink: Battle for Atlas) in the English version, and Kunpei Sakamoto in the Japanese version.

In Japan, Andrew Oikonny's name is アンドリュー・オイッコニー (Andoryū Oikkonī).

His surname seems to be a pun on the Japanese word for nephew, 甥っ子 (Oi-kko). Obviously this is a pun/reference to the fact that Andross is canonically Andrew's uncle.

Star Fox, Star Fox 64 and Star Fox Adventures are the only Star Fox titles to provide official ages for the main characters, primarily within their Japanese ancillary material. In the Original Soundtrack box released for the first game, Fox, Falco, Peppy and Slippy are said to be 25, 28, 36 and 19 respectively. Star Fox 64, being a remake of the first game, would retcon these ages and make Fox 18, Falco 19, Peppy 41 and Slippy 18.

The "Farewell Beloved Falco" midquel manga, which is set right in the middle of the eight years between Star Fox 64 and Star Fox Adventures, also gives the original Star Fox crew ages, with Fox now being 22, Slippy 22, Falco 23, and Peppy 45.

Star Fox Adventures takes place eight years after Star Fox 64, which means that Fox is now 26, Falco 27, Peppy 49 and Slippy 26. Japanese Star Fox Adventures ancillary material also reveals Krystal's age to be 19, making her distinctly the only Star Fox character outside of the original four Star Fox members to have a known age. Going by this, she would be 11 and 15 years old during the events of Star Fox 64 and Farewell Beloved Falco, respectively.

After Adventures' release, Nintendo, specifically Takaya Imamura, made a deliberate decision for future Star Fox games to not provide any official age numbers for any of the characters. However, Star Fox Assault officially is said to take place only year after the events of Star Fox Adventures, so this would make Fox 27, Falco 28, Peppy 50, Slippy 27, and Krystal 20. Similarly, according to Takaya Imamura in a 2007 interview, Star Fox Command takes place 2-3 years after Assault, which would make Fox 29-30, Falco 30-31, Peppy 52-53, Slippy 29-30, and Krystal 22-23.

Although Wolf O'Donnell has never had any age officially listed for him, Takaya Imamura implied on Twitter that he is within the same generation of Peppy and James.

In Japan, Slippy Toad's father, Beltino, is called ベルツィーノ(Berutsīno) which comes from ベルツノガエル (Berutsunogaeru), meaning Bert's frog or Belted frog. This is also the Japanese name for the Argentine horned frog, better known as a Pacman frog. Funny enough, after being alluded to on the Japanese Star Fox 64 website, Beltino would go on to have a major role in Star Fox: Assault, which was developed by Namco, the creators of Pac-Man.

It would seem the entire overall story of Star Fox 64, and also its reimagining, Star Fox Zero, spans about 10 years.

Going by the manuals and guidebooks, the story begins with Andross being banished to Venom by General Pepper after he unleashed a deadly weapon of some kind upon Corneria. Five years later, the original Star Fox team are sent to investigate strange happenings on Venom only for its leader, James McCloud, to be betrayed and killed by Pigma Dengar, which was also meant to be Andross' declaration of war upon Corneria and the Lylat System, and he and his new army he build up over time would spend the next five years attacking them, leading to General Pepper calling upon the new Star Fox team, which leads directly into the events of Star Fox 64.

Curiously, most of SF64's ancillary material leave it vague on how long it's been between James' death and the events of Star Fox 64, typically only saying that "several years" have passed, all except for Pigma's biography in the official Japanese Star Fox 64 guidebook, which makes it more clear that it's been five years since he betrayed James and Peppy. Beta Star Fox 64 images, as well as the lost developer dub discovered in the Nintendo Gigaleak from 2020, show that Peppy was originally meant to have a line on Titania where he says "This reminds me of 10 years ago!”, obviously referring to when Andross nearly eradicated Corneria with his bioweapon, which is what led to his banishment to Venom in the first place.

Star Fox Zero, whose story and lore is almost completely identical to Star Fox 64, fully verifies that it's been indeed five years since James' death and also overall 10 years since Andross was banished to Venom, both through its opening prologue, the Star Fox Zero - The Battle Begins animated short that was created to commemorate its release, and also the official Japanese Star Fox Zero website.

Contrary to popular belief, and also contrary to the Star Fox 64 Official Player's Guide, Solar is not a star, but merely a lava planet with an exposed mantle, according to both the official Japanese guidebooks for Star Fox 64 and Star Fox Command. Even the official Western Star Fox 64 website clarifies it being a planet. The Western localization of Star Fox Command would also reiterate this in-game, with one of its missions on Solar being named "The Red-Hot Planet".

In a 2011 Nintendo Dream magazine interview with the Star Fox 64 3D development staff, Takaya Imamura once again clarified that Solar is a planet, and that the star Lylat exists somewhere in the Lylat System not visible on the map screen. Apparently, the development team did consider changing Solar into being a sun for Star Fox 64 3D, but this was passed over.

The boss on Solar known as Vulcain, alternatively known as サンガー (Sangā) or Sanger in the Japanese version of Star Fox 64, was originally intended to be the boss for Sector X.

A developer story on the Japanese website for Star Fox 64 reveals Sector X was originally meant to be the "Andross Army Biological Weapon Development Factory", and Fox and his crew were supposed to have engaged with a transport fleet heading for the factory, where they would sneak past the security defenses and enter the interior of the factory, only to find it in a state of disarray due to an accident during an experiment with robots and out-of-control bioweapons attacking all over. They would eventually come across an enemy transport ship attempting to escape only for it to be suddenly destroyed from the inside, revealing Vulcain as the stage's boss.

In the final game, Spyborg (HVC-09 in the Japanese version) is the boss of Sector X, and Vulcain was relocated to planet Solar. Vulcain's beta textures from its tenure as the Sector X boss was recently discovered within files pertaining to Star Fox 64 in the Nintendo Gigaleak.

The official Japanese Star Fox 64 guidebook reveals that Pigma Dengar, who became a subordinate of Andross, was effectively the real mastermind behind the creation of Star Wolf: he goated and manipulated Wolf into becoming its leader and also working for Andross as a means to combat the newly formed Star Fox team led by Fox McCloud, taking advantage of Wolf's supposed honorable, "magnaimous" side and also his prior rivalry with Fox's father, James McCloud. It is said that he manipulates the entire team behind the scenes in accordance to Andross' orders. It also reveals that Pigma had already been working underneath Andross during his time as a researcher at the Corneria Defense Force Scientific Research Institute. It's also revealed that both Pigma and Andross had custom engineered the Wolfens that the Star Wolf team utilize in their battles against the Star Fox team's Arwings.

In Super Smash Bros. 4, the trophies for Pigma and the Wolfen would reiterate this information, as would the official guidebook for Star Fox Command. The Star Fox 64 Official Player's Guide would similarly allude to Pigma being the root cause of Fox and Wolf's rivalry, claiming that, without his influence, perhaps they could have been friends in another timeline.

The official Japanese Star Fox 64 guidebook reveals that Andrew Oikonny was essentially forced onto the Star Wolf team purely out of nepotism on Andross' part, and that he was actively disliked by his teammates due to his poor piloting skills and also massive ego in regards to his relationship with Andross. Effectively, the only reason Wolf put up with him during the events of Star Fox 64 was due to the fact that he was using said connections to Andross to provide his team with immeasurable technological and financial backup.

A timeline of events provided in Star Fox Command's official guidebook claims that after Andross' defeat at the end of SF64, the Star Wolf team moved away from the Venom army effective immediately and in turn kicked out Andrew, who no longer had the support of his now deceased uncle, hence why at the beginning of Star Fox: Assault, he's on his own trying to rebel against Corneria using the remnants of Andross' forces.

Prior to Star Fox Zero, there were two attempts in previous installments to revitalize the concept of the Walker from Star Fox 2, or at least the idea of the Arwing transforming into a robot form, those specifically being Star Fox 64 and Star Fox Command, games that both aimed at preserving ideas from the then-long-lost Star Fox 2.

• For Star Fox 64, according to Shigeru Miyamoto in an interview at the end of the Star Fox 64 Official Player's Guide, he wanted to have the Arwing transform into "a human-type craft". This was rejected by other staff members of the SF64 development team. In response, Miyamoto told his team to come up with better ideas, and from there they created the Landmaster and Blue Marine for additional vehicles.

• For Star Fox Command, according to Takaya Imamura in an interview in 2007, the dev team experimented with having the Arwing and other spacecraft transform into robots, but this was ultimately dropped.

According to the brochures distributed with Star Fox 64 3D in Japanese retail stores in 2011, it was Pigma Dengar who designed the Star Fox logo during his tenure with the original team, before he betrayed them.

Katt Monroe, a female feline character who first appeared in Star Fox 64, had undergone a notable change in appearance from that game going into Star Fox Command, most notably now having black fur instead of pink. According to Takaya Imamura in a 2011 Nintendo Dream magazine interview, he changed her appearance to be more "fashionable".

Star Fox Adventures notably takes place eight years after the events of Star Fox 64. In an interview with Nintendo Official Magazine in 2002, Takaya Imamura admitted that he felt it'd be better for Fox and his friends to grow and change over time, as opposed to other Nintendo characters like Mario and Bowser who never age.

Imamura would touch upon this again in an 2002 Nintendo Dream interview regarding Star Fox Adventures. In addition to wanting to come up with a justification for why Fox, Falco, Peppy and Slippy would reunite to fight the enemy, he also wanted to reflect the change in genre from SF64 to SFA and how the relationships between the characters had evolved since then.

As mentioned in the same interview, Imamura had already stated some years prior he'd like to make a sequel to Star Fox 64 taking place 20 years later (Fox would be 38 years old) in the official Japanese guidebook for Star Fox 64 released in 1997.

On the Japanese website for Star Fox 64, Slippy mentions certain background characters who would appear in future installments:

• Peppy's wife, Vivian Hare. According to Slippy, Peppy took her to planet Zoness for their honeymoon, which explains why Peppy is so distraught at its polluted status in SF64. Vivian would appear in-game for the first time in Star Fox Command, where it's revealed that she and Peppy had a daughter named Lucy, and that Vivian had died of a disease several years prior.

• Slippy's father, Beltino Toad. According to Slippy, Beltino works as an engineer for Space Dynamics, the manufacturer of the Arwing and many of the other vehicles the Star Fox team utilize. Beltino would later appear in-game for the first time in Star Fox Assault, and would later appear in Star Fox Command.

It's worth pointing that unlike Vivian, Beltino was mentioned in western ancillary SF64 material, that being both the official western Star Fox 64 website and the Star Fox 64 Official Player's Guide, where it states that he helped his son Slippy create the Blue Marine.

Much like the original Star Fox on Super Nintendo, Star Fox 64's stages are split into three difficulty routes: Easy, Normal and Hard. However, unlike the original, SF64 only features two versions of Venom, one for the Easy Route and one for the Hard Route, the latter of which is where the Star Fox team has a final rematch with their rivals, Star Wolf.

It turns out the development team had planned on including another variation of Venom for the Normal route, where Fox McCloud would jump out of his Arwing and battle Andross on-foot with a bazooka. According to the staff, this was scrapped due to time constraints. The pilot mode option seen in Star Fox 64's battle mode is actually the repurposed remnants of this idea.

The green planet Peppy's Arwing is shown hurdling towards in the prologue for Star Fox 64 (and also its 3DS remake, Star Fox 64 3D) is actually meant to represent Papetoon, his and also Fox and James' home planet. The Japanese prologue even refers to it as such, and various Japanese SF64 material also mention it. However, when Star Fox 64 was localized for Western audiences, Nintendo of America completely wiped out all specific mention of Papetoon in both the prologue and also manuals/guidebooks.