Today marks a major milestone for Captain America and the U.S.A. It's the 4th of July and it's Steve Rogers' 101st birthday, which means he's getting a ton of attention on social media. And while turning 101 is a major deal, Avengers: Endgame introduced Marvel Cinematic Universe fans to a new side of the hero: his backside. Chris Evans dubbed it, "America's Ass," in the movie and it has stuck from getting real birthday wishes on social media to getting them as Steve Rogers.

The now famous Avengers: Endgame line came when Scott Lang, Tony Stark, Bruce Banner, and Steve Rogers went back in time to the Battle of New York. Rogers ended up having to battle himself, which was a lot harder than he initially thought. After he prevailed against his past-self, Rogers turned and looked at his backside, admiring it and coining the phrase everybody is now using on the 4th of July to celebrate the hero's birthday. One MCU fan said, "The Fourth of July is about three things. Freedom. Patriotism. And Ass!"

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The Russo Brothers, along with Avengers: Endgame screenwriters Stephen McFeely and Christopher Markus probably had no idea the line was going to take off like it did. It's now something Chris Evans cannot get away from, though he really doesn't seem to mind at this point in time. He has been seen posing for pictures with fans who are obviously going to post something about Captain America's backside when it goes online and today is the day to let all of those pictures pour out.

Captain America was born July 4th, 1918 and he was first introduced in Captain America Comics #1 in 1941. However, it wasn't until the 1960s when the character became a household name for comic fans. As for figuring out when the hero's birthday is, Captain America: The First Avenger gives us a quick glimpse of his medical records when he attempts to sign up for the Army. With that being said, the comic book version of Cap was actually born in 1917, which makes him 102 years-old in that universe. But as far as the MCU is concerned, he's still only 101.

For fans looking for ways to celebrate the 4th of July and Captain America's birthday, Avengers: Endgame is still in theaters and great way to remember "America's Ass." Marvel Studios recently rereleased the epic movie in theaters in an attempt to take down James Cameron's Avatar as the highest grossing movie of all time. As of this writing, the movie is about $20 million short of that goal, but all of this birthday attention for Cap could get the movie even closer by the end of this weekend. Even Chris Evans' Endgame co-star Mark Ruffalo got in on the backside fun. Mark Ruffalo's Twitter birthday message and some from the fans can be seen below.

Kevin Burwick at Movieweb
Kevin Burwick