Updating all the time. I'll probably re-organize this whole page soon and maybe split it into a few, so look out for that.

General information
General info. Has a working tag and search system and a category dedicated to the Balkans.
Sorted by country. Has most countries, excluding Russia.
tumblr blog that compiles Eastern European art, architecture, traditional clothing, and more. Sorted by country/culture and category by way of tumblr's tagging system.
Slavica publishers' 50th anniversary reissues
50-year-old texts now up for free download in PDF format, no strings attached. Obviously somewhat outdated, but much is still useful, and, again, it's free. The Gods of the Ancient Slavs is particularly useful for anyone curious about East Slavic paganism - and I would especially recommend sticking to academic sources when you start out with this type of research, as there's a lot of grifters surrounding the subject.
Folk Costume & Embroidery
Blogspot about, you guessed it, folk costumes and embroidery. Blog is active and has shared sources on stuff when asked before, so a great starting place if you don't know what you're looking for.
a community-run website that hosts translations of songs' lyrics into other languages. Great if you're like me and like listening to stuff from anywhere! If you're bilingual, you can submit translations as well.
The Gutenberg Project
Digital library of books in the public domain. Can be read on the website themselves or downloaded as PDF. Search function allows for filtering by language.
Eastern European Movies
place to watch Eastern European movies with subtitles online, for free.

Tradycyja / ЭтнаТрадыцыя
Belarusian facebook group for cultural education.

Bulgarian National History Museum website
Народни носии от Видински окръг
Photos scanned from the book posted to Facebook by Bulgarian national dress. Click on any specific photo to find out what region or village something is from.
Bulgarian Folk Costumes - Symbols and Tradition
by Radoslava Ganeva (Internet Archive link)
History of Bulgarian Costume
by Vanera Naslednikova (Internet Archive link)
Album of Bulgarian and Macedonian Embroideries
by Raina Roumenova

Budapest's Iparművészeti Múzeum's website
Hungarian online photography magazine. Available in Hungarian and English language.

City museum, Tychy, Poland
Has links to two specific photographers' works right now, but you can find more by clicking the filters in the dropdowns on the header before clicking the search button on the search bar. The color photography section ('fotografia barwna') has lots of photos of people wearing traditional clothing.
Museum of Modern Art in Warsaw
Polish Folk Costumes
An educational blog, collecting reference images of regional costumes in Poland.
Polska na fotografii
Polish photography archive
Lamus Dworski
"Uncovering Poland: culture, folklore, history, archaeology, arts, curiosities, and more."
Polska Tradycja
Polish website about Polish culture. Most information seems to be sorted by region. Has pictures and descriptions of traditional clothing.
Folklore museum of Sieradzu online gallery
Stroje Ludowe
folk clothing references sorted by region
Polish film photography website

Biblioteca digitală a publicațiilor culturale
Romanian digital library of cultural publications
SEMNE CUSUTE in actiune
Romanian facebook group about traditional embroidery.
Arhiva de Fotografie
Facebook page that shares a lot of vintage Romanian photographs.
Enciclopedia României
Encyclopedia Romania
Ethnographic museum of Brașov
Semne Custe (blogspot)
Blog about Romanian embroidery. Unrelated to the Facebook group as far as I know.
L'art Paysan Roumain
Internet Archive link. A French-language book of Romanian art and folk clothing uploaded by Mioritic. They have an extensive gallery of stuff found in Bucharest as well if you want to look through their profile.
Transylvanian Folk Costume Embroidery by Helen Hough
Internet Archive link

Russia and the Soviet Union
Harvard's Digital Handbook for Research on Soviet History
Russian Art and Soviet Nonconformist Art collection, Zimmerli Art Museum, New Brunswick, NJ, USA
The Museum of Russian Art, Minneapolis, MN, USA
Despite the name, includes both Russian and not-so-Russian Soviet art. If you're ever in Minneapolis, visiting TMORA is the best thing to do with your time. Their online gallery is mostly just drawings, paintings, prints, et cetera and doesn't include stuff like their temporary showcases or other types of art/artifacts.'s traditional costume section
lenty of articles on Russian clothing, generally sorted by region.
Camelot Club
LiveInternet group with a ton of blog posts about history, music, traditional costume, and Russian culture
blog about Russian traditional costume and contemporary fashion
website dedicated to Soviet rock bands. Check out the "Поиск групп" page for a list of bands with releases logged on the site!
Traditional Russian Costume
Blog about exactly that.
The Russian Fashion Blog
Has a section dedicated to historical fashion. Also posts about contemporary fashion. Last updated in 2014.
Translated materials and heavily sourced English-language articles regarding Russian medieval culture and history
Playing Soviet: The Visual Languages of Early Soviet Children's Books, 1917-1953
Princeton University's online library of Soviet children's books. Great for anyone looking for starter reading practice as well as anyone interested in Soviet illustration and art history.
Russkaya fantastika i fantastika v seti
Old website about Russian fantasy and science fiction books. There's some free stuff to be found rooting around on here, including stuff in English.
Roadside Picnic
An English translation of Roadside Picnic by Boris and Arkady Strugatsky. I recommend this book to anyone and everyone. The earlier translation is available on the Internet Archive if you're more interested in that one.
Seventeen Moments in Soviet History
an online archive of primary sources maintained by Michigan State University

Russian language
As a note please remember to check the above section for extra resources for exposure!

Textbooks (all links lead to the Internet Archive)
A Comprehensive Russian Grammar and A Comprehensive Russian Grammar Workbook
by Terrence Wade
The Russian Language Today
by Larissa Ryazanova-Clarke and Terrence Wade
The Oxford Russian Grammar and Verbs
by Terrence Wade
Russian English Bilingual Dictionary
by DK

Online dictionaries
What I'd recommend always checking first! Just set the language to your first and look up the word in Russian. Pages include a pronunciation recording, grammar charts for endings, notation on which vowel is stressed, and more.

Eugenia Vlasova's blog. She sells some language resources but also posts free-to-read articles about Russian language concepts, particularly things that may not be included in textbooks as much.
Russian Lessons dot net
Where I started learning Russian. Has pages describing basic grammar stuff and a couple games for memorizing certain parts of the vocabulary.

Russian Made Easy with Mark Thomson
Great beginner stuff.
Understanding Spoken Russian with Mark Thomson
Also great beginner stuff. Explains grammar in a way that makes it easy to understand very quickly.
Пять минут by Eugenia Vlasova
5 minutes of Eugenia talking in Russian about a set topic each episode. She talks at her natural pace so it can seem kind of fast, this probably isn't going to help you if you're only just starting out.

check pronunciation using user-submitted voice clips
check pronunciation using YouTube clips
Collaborative website collecting sentences in different languages, sorted by language. Can be used to build flashcard decks (I don't personally recommend making decks out of individual words, but full sentence ones are useful)

Ivan Honchar Museum, Kyiv, Ukraine
Collections of paintings, old photographs, clothing, rushnyky, and more. Includes what region the item was made in wherever possible in its individual page.
Lviv Skansen museum online archive
Sorted by exposition.
Canadian Institute of Ukrainian Studies' Internet Encyclopedia of Ukraine
Managed by academics & generally has more information than English language wikipedia on many subjects
Ukrainian embroidery patterns
free embroidery patterns site with a section for Ukrainian styles
The Meaning Behind Traditional Patterns in Ukrainian Embroidery
Textova vishivka
A little website that can generate you a geometric vyshyvanka pattern based on any name you type in. Converts alphabet input into Ukrainian cyrillic, so it may have difficulty with some letters.
an online library of publications regarding Ukrainian culture and history.