Superman has inspired generations of fans since his heroic first appearance in 1938. Kal El’s emergence into pop culture sparked a revolutionary new concept, the superhero and thousands of colorful characters soon followed in his wake.

Superman was first created by Joe Shuster and Jerry Siegel in 1933, however the character wasn’t popularized until his successful debut in “Action Comics no. 1.”
The Metropolis Marvel made his heroic first appearance in his iconic red and blue ensemble within the pages of Action Comics No. 1, which first hit stands in April 1938.

Secret Orgins
Many speculate that Superman is celebrated in June due to the iconic first issue’s publication date, but that’s only a small coincidental portion of this dates history.

Before DC Comics made the date official in 2013, June always saw some sort of celebration in honer of the Man of Tomorrow.
The actual city of Metropolis, Illinois has celebrated their favorite son since 1978, usually in the last week of June. Unfortunately this years Superman Celebration has been canceled due to COVID-19 concerns.
Some speculate Metropolis’ Superman Celebration could also play a small part in June 12 being decided as Superman Day, but their celebration date was just a lucky coincidence.
Superman Day’s secret origins actually start with Zack Snyder’s 2013 blockbuster, “Man of Steel.”
In celebration of the summer’s most eagerly anticipated film, DC Entertainment is partnering with comic book retailers and bookstores across America to declare Wednesday, June 12 MAN OF STEEL DAY, ahead of the film’s wide release on Friday, June 14
Official statement from DC Comics News, May 21, 2013
Due to the high anticipation of “Man of Steel,” DC Comics listed June 12 as “Man of Steel” Day. It later evolved to Superman Day.
Since “Man of Steel,” the date has been celebrated by fans annually.
Superman Day may have been influenced by numerous factors, but it was “Man of Steel” that popularized the date further.
Superman Day on Twitter

How to celebrate Superman Day
For those aspiring to celebrate Superman Day, there’s a large variety of possibilities. Consider sitting down with your favorite Superman comic, or watch your favorite Superman film/TV show. Maybe even adopt Superman’s heroic ideals and seek justice.
We are living in historic times that calls each and every one of us to don the cape. Honor what Superman stands for by seeking out the truth and demanding justice. Save lives by practicing safe social distancing, donating blood and so much more. The opportunities to be a little bit “Super” are limitless.
Go out and save the world.