Thanks to Jack from Jacksfilms on piano: https://youtube.com/jacksfilms • And thanks to everyone who answered! Sources and a data download are in the description.

History sources:
https://www.cracked.com/blog/the-secret-true-history-jingle-bells-batman-smells/
https://www.cbr.com/jingle-bells-batman-smells-secret-origin/

Data spreadsheet link:
https://docs.google.com/spreadsheets/d/1bVUdszCBsWn5ez9FPFCioirdyNeZu3ctvNYShExpTQo

Audio mix by Graham Haerther: https://haerther.net

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