Bridgerton · A Viewer's Companion
The trick to Bridgerton is that the family did the work for you: the eight siblings are named alphabetically, in birth order — Anthony to Hyacinth. Everyone else sorts by household: wisteria blue borders are Bridgertons, citrus is the scheming Featherington house across the square, and teal marks the Sharmas and everyone who married in. One dashed line holds the show's biggest secret.
Bridgerton has no war and no dynasty dispute. What it has is a very large family, three households, and one anonymous writer stirring them all.
Violet and Edmund named their children alphabetically: Anthony, Benedict, Colin, Daphne, Eloise, Francesca, Gregory, Hyacinth. If you ever forget who's older, the alphabet is the answer — Anthony is the eldest and the viscount; Hyacinth is the baby of the house.
The show marries off one Bridgerton per season: Season 1 is Daphne (and Simon), Season 2 is Anthony (and Kate), Season 3 is Colin (and Penelope) — with Francesca's quiet courtship of John Stirling tucked into Season 3 as well. Benedict is next. Whoever gets the letter, gets the love story.
The anonymous scandal sheet narrated by Julie Andrews is written by Penelope Featherington — the wallflower nobody in the ballroom notices. Viewers learn it at the end of Season 1; Colin and the whole ton only find out in Season 3, after Cressida Cowper falsely claims the name for herself.
Anthony spends Season 2 formally courting Edwina, the season's "diamond" — while falling for her older half-sister Kate, who came from India only to chaperone. Edwina halts her own wedding when she sees it. Note the family fine print: Lady Mary is Kate's stepmother, not her mother, which is why Kate carries the burden of the family alone.
The spin-off Queen Charlotte: A Bridgerton Story jumps back decades to the Queen's marriage to King George — and shows young versions of Violet and Lady Danbury. It explains why the Queen runs the marriage market like a blood sport, and why Danbury answers to no one.
Three households, a lot of daughters, and several people who change names mid-show. Keep these apart:
Best friends on opposite sides of the square. Penelope = Featherington (citrus), secretly Whistledown. Eloise = Bridgerton (blue), loudly anti-marriage. Their falling-out — Eloise discovers the secret at the end of S2 — powers most of Season 3.
The Sharma sisters. Edwina is the one Anthony courted; Kate is the one he married. If someone is arguing with Anthony, it's Kate. If someone is being paraded before the Queen, it's Edwina.
All three Featherington daughters have P-names (their mother would never be out-alphabeted). Prudence marries Mr. Dankworth, Philippa marries Mr. Finch, and Penelope — to Portia's amazement — marries a Bridgerton.
Archibald (Ben Miller) dies at the end of Season 1 over his gambling scheme. The "new Lord Featherington" of Season 2 is cousin Jack — a conman with fake ruby mines whom Portia outschemes and ships off to America.
Not a new character — a recast. Francesca was played by Ruby Stokes in Seasons 1–2 and by Hannah Dodd from Season 3, when she finally gets her own storyline with John Stirling.
Why Simon outranks everyone: Duke (Simon) > Earl (John) > Viscount (Anthony) > Baron (Featherington). That's also why Daphne "marrying up" to a duke is Season 1's coup, and why the Featheringtons fight so hard for status.
In Season 3 Cressida Cowper publicly declares that she is Lady Whistledown, to claim the Queen's reward. She isn't. Penelope's counter-move — unmasking herself in print — ends the whole game.

Crowns each season's "diamond" and treats unmasking Lady Whistledown as a personal vendetta. Her own love story with King George is the spin-off.

Society's kingmaker and its sharpest cane. Simon's guardian in Season 1, the Sharmas' sponsor in Season 2, and the Queen's oldest friend.

A distant Featherington cousin lodged with Portia in Season 1 — secretly pregnant, she nearly married an unknowing Colin before Whistledown exposed her. Later Lady Crane.

The resident mean girl, briefly Eloise's friend — and Season 3's fake Whistledown, whose gambit for the Queen's reward gets her exiled to an aunt in Wales.
Scope and spoilers: this chart covers Bridgerton through the end of Season 3 — and it does not tiptoe. The identity of Lady Whistledown (a Season 1 reveal for viewers, a Season 3 reveal for the characters) is printed right on the tree, along with every marriage through Season 3. Portraits are stills from the Bridgerton wiki, cropped and served from this site — nothing hotlinked. † marks characters dead within that scope.