The holiday calendar is filled with dates that are not recognized by the U.S. government. But there is one that is celebrated on May 4 that has an intergalactic and Hollywood feel: Star Wars Day.

So, why was May 4 the date to celebrate the sci-fi fantasy franchise? The phrase “may the force be with you,” used by the character Obi-Wan Kenobi, sounds a bit like "may the fourth be with you."

Ahead of a Disneyland theme park that was set to open in May 2019, the California Legislature became the first governing body to officially recognize May 4 as Star Wars Day.

“Like anything that emerges from the collective passion of a group of people, the Star Wars fan holiday on May the 4th each year has no single point of origin. It has no official commencement year, no formal dedication,” the Star Wars website said Tuesday in a release.

“It is a grassroots phenomenon that now transcends the English language pun that inspired it. Around the world, 'May the 4th Be With You' is more ubiquitously known as 'Star Wars Day,'" it added.

The phrase originated from “Star Wars: A New Hope,” which was released in 1978.

Star Wars said in its release that it has evidence that one year after the movie's release, Star Wars became engraved into American pop culture “like a handshake.”

Considering Star Wars’ massive impact on American culture, “the laughable pun continued to circulate underground, an unofficial holiday emerged,” the release said.

This has now led dedicated Star Wars fans to have a whole day to celebrate or hold themed parties and events.

Star Wars also kicked off the May 4 celebration this year with the release of the new Obi-Wan Kenobi trailer.