Vinsmoke Family

The Vinsmoke Family is a powerful and infamous family of Underworld killers, and the family from which Sanji hails. They are a family of royalty which once ruled the entire North Blue, and are now primarily known for their Underworld activities as the commanders of the paramilitary organization Germa 66.

Overview
The Vinsmoke Family is a family of killers that commands the Underworld army known as Germa 66; Germa 66 is so technologically advanced that even the Yonko Charlotte Linlin is interested in them.

In the past, the Vinsmokes managed to conquer the entire North Blue with their military might. Although they no longer rule over a kingdom, they still possess the authority and privileges of royalty, including the right to attend Reverie. Furthermore, their patriarch is powerful enough to directly influence the bounty system, by both increasing bounties and even changing their conditions of capture.

The Family currently conducts its primary operations within the Underworld, although the exact nature of its activities is unknown. Its prominence and infamy throughout the Underworld is great, but its notoriety seems to extend beyond its parameters, with Brook and Robin both recognizing the Vinsmoke name.

Members
The family is currently known to consist of a father (the family patriarch), at least four sons (of whom Sanji is the third), and at least one daughter. The patriarch is known to be an infamous man throughout the New World.

The family's most distinct physical feature is their curly eyebrows, both of which swirl in the same direction; this makes them asymmetrical.

Past
Sometime in the past, the Vinsmoke Family ruled all of North Blue with their military might. Presently, while they no longer rule over any land, they still retain the influence and status of royalty. There is a fictional tale, circulated in comic strip form, that depicts their conflict with the Marines.

Sometime before he was nine years old, Sanji migrated across the Red Line from North Blue to East Blue: a considerable journey, given the geographic circumstances. When Sanji was at the age of nine, the cruise ship he was on was attacked by the Cook Pirates, and then sunk in a storm. Sanji and the pirate captain, Zeff, were marooned on an island, where they almost starved to death. After their rescue, Sanji worked under Zeff as they built the Baratie, with Sanji becoming the sous chef. Ever since Sanji left the family, his father has been searching for him.

Ten years later, Sanji left Baratie to join the Straw Hat Pirates, taking part in their pirate activities and earning the attention of the World Government. When he received his first bounty, there was no photograph of his face, so a crude drawing was substituted instead. Because of this drawing, the Marines that Sanji's father sent went after Duval instead. However, when Sanji received his second bounty two years later, it contained a picture of his real face and Sanji's father ordered the change of bounty condition from "Dead or Alive" to "Only Alive".

Zou Arc
Some time between the Curly Hat Pirates' encounter with the Big Mom Pirates off the coast of Dressrosa, and the Big Mom Pirates' arrival on Zou, the Vinsmoke and Charlotte Families entered into a political alliance, to be sealed with an arranged wedding between the third Vinsmoke son, Sanji, and the 35th Charlotte daughter, Purin. Sanji, shocked that his past had been brought up again, believed that his family were also responsible for the change in his bounty condition of capture. With the intention of putting an end to his past, Sanji reluctantly left Zou to meet with his family at Whole Cake Island.

Whole Cake Island Arc
Luffy and the Sanji retrieval team first encountered Germa 66's ship, with Yonji and Reiju in command, as they entered Big Mom's territory. The team initially mistook Yonji for Sanji, due to the similarities in their appearance, but Yonji announced himself to the team aboard the Thousand Sunny. After observing the dying Luffy and refusing to hand over an antidote for Luffy's poisoning, Reiju intervened and cured Luffy by absorbing the toxin. After a brief encounter, she and Yonji returned to their ship and agreed not to report the team's presence, out of concern that it might jeopardize the wedding plans.

Trivia

 * The Vinsmoke Family's naming convention, based off the names of the known Vinsmokes, appears to follow the pattern "(number) + j + vowel": Rei(0)ju, Yon(4)ji, and San(3)ji.
 * Although all known members of the Vinsmoke Family share the characteristic curled eyebrows, Sanji is currently the only known member with eyebrows that curl in a clockwise direction (to the right side of his face), while the others curl counter-clockwise (to the left side of their faces).
 * All known members of the Family have an Epithet with a color in their name. However, Sanji's epithet (黒脚) varies fundamentally from the others because it is written in kanji, not katakana.
 * It is very likely that the name "Vinsmoke" is a portmanteau of "vin" (the french for "wine") and "smoke"(a reference to Sanji's characteristic of smoking).