Feathers For Castiel

Feathers for Castiel was a fan campaign that ran from the end of January into February 2013, during Season 8.

The campaign originated in a post by mapalap on Tumblr which in part read:

Feathers for Castiel is a campaign aimed at the powers that be to make them realise that the fandom wants characters such as Castiel to be recognised as important parts of the show, wants a deeper plot, wants a mytharc for Dean, wants Cas to be a more important part of the show, wants more recurring, strong female characters who are not there for their sexual appeal, wants a better show. There are parts of the fandom that simply aren’t happy with how things are going.
The show’s idea of two co-dependent brothers with no family, no friends and no reasonable storyline is NOT a good show idea, it will not last. To ensure its longevity, Supernatural needs to listen to its fans, and not just the brothers’ fans.
To be a part of the campaign and show your support of Castiel and other supporting characters, simply write in big, bold letters on a piece of paper “Feathers for Castiel” and put it in an envelope. Also put a feather (or many) in the envelope, white if possible but any colour if you can’t find white. Include a letter behind the bold note if you like, expressing your opinion, and then seal the envelope and send it to this address:

Supernatural Cast & Crew Supernatural Films Inc. 8085 Glenwood Drive Burnaby, B.C. V3N 5C8 Canada

If you want a show that encourages healthy character development, listens to its fans, creates storylines that have strong, interesting arcs, and supports it’s supporting characters, get involved with Feathers for Castiel now. When you have sent your feather, post on Twitter or Tumblr under the tag #FeathersForCastiel

Letters should be sent so they arrive at their destination on the 27th of February, or as close as you can get to it. Talk to your local post office to find out when you should send it.

Check your local craft stores and supermarkets for feathers. If you want to send a box of feathers or go even more extreme, feel free.

Time is running out.

A blog by justacasgirl also cited quotes from Producer Bob Singer as proof that the showrunners thought fans did not want to see more ensemble characters:

Singer talking about female characters and other side characters “I don’t think there’s ever going to be a third wheel.” “It’s been sort of the feedback that we get that that’s not something that the fanbase particularly likes.” SOURCE

Singer talking about why Purgatory was only shown in flashbacks “Because fans usually hate it when the brothers are separated, so that’s why they’re being reunited quickly." SOURCE

A tweetstorm using using #FeathersForCastiel was planned for February 27th.

Fans commenced sending feathers - notably to the set, not to the writers in LA. However on 21 February production Assistant Tara Larsen tweeted "We appreciate your enthusiasm for the return of Castiel #spn but please stop sending feathers as some people myself included are allergic." which brought the campaign to a slightly early conclusion.

Interestingly it was on 26 February that it was announced that Castiel would again be promoted to a season regular for Season 9. Misha tweeted "I don't think the feathers to the offices campaign was what saved the angel, but it does look like i'm going to be a regular for season 9."