So.. this is purely self declared but I’ll do it anyway. I only added birthdays that were officially named by Himaruya.
February 3: Neko Day (Greece)
February 11: Sakura Day (Japan)
February 12: Tomato Day (Spain)
February 16: Something Something Day (Lithuania)
February 24: Duuuh (Estonia)
February 28: Uhhh (Egypt)
March 17: Pasta Day! Ve~ (N. Italy)
March 17.5: Oishi Tomato Day (S. Italy)
April 17: Axis Powers Day
April 18: Mochi Day
April 19: USUK Day (Although… it’s kinda everyday but I felt the need to do it anyway!)
April 20:
April 21: Nekotalia Day
April 22: HetaMVI Day
April 23: HetaMVII Day
April 24- May 2(extended to May 27 lol): Jaden Invasion (Sandals banned until work is done).
May 20: MIA (Cuba)
May 27: Asia Day- excluding Russia)
June 6: Misunderstood Day (Sweden)
June 8: Fujoshi (Hungary)
June 17: Hmm… (Iceland)
June 29: Fish? (Seychelles)
July 1: Maple Day (Canada)
July 4: HAMBURGER DAY!!!!! (America)
July 12: Onii-chan Day (Lichtenstein)
July 14: Rose Censorship Day
August 1: Neutrality Day (Switzerland)
August 15: Your Breasts are Mine Day (S. Korea)
August 24: Vast Tracks of Land Day (Ukraine)
August 25: Marry Me Day (Belarus)
September 2: (Sealand)
October 25: Asianess (Taiwan)
October 26: Classical Music Day
October 29: Mask Day (Turkey)
November 11: Ehe (Poland)
November 18: Get A Clue Day (Latvia)
December 6: Santa Day (Finland)
December 30: KolKol Day