The pair helped kick off the multi-sport event for wounded, injured or sick armed services personnel at Walt Disney World's ESPN Wide World of Sports Complex in Orlando, Florida.
While addressing ceremony attendees and competitors, the prince said that he felt like he was "at home" while looking at the faces of fellow servicemen and women.
"I learned about the importance of teamwork and camaraderie that only military service can teach you," he said. "I joined the army because for a long time I just wanted to be one of the guys."
While highlighting the injured men and women competing in the games, Harry also took a moment to highlight those veterans (and non-veterans) who were struggling with invisible injuries like mental health issues, something he touched on before the Games.
"Let's cheer for the woman who fought through post traumatic stress and let's celebrate the soldier who was brave enough to get help for his depression ... They weren't too tough to admit that they struggled with mental health."
After his rousing speech – which was occasionally punctuated by laughs and knowing smiles at those in the audience – Harry handed off to Obama, who thanked the royal for his work with the Games.
"He is truly our Prince Charming isn't he? He should be proud of himself for his work," she said."
The Invictus Games include 10 different events like wheelchair basketball, sitting volleyball, and indoor rowing, and are similar to the U.S. Warrior Games. Harry launched the international competition in 2014, and it has since grown to over 500 competitors from 14 countries.
Also present for the opening ceremonies were British musician James Blunt and American actor Morgan Freeman.
While performing, Blunt joked about Harry's heartthrob status while introducing "You're Beautiful."
"I want to dedicate this song to Harry because he's hot but there's someone here's who's just a little bit fitter than him so I'd like to dedicate this song to your First Lady, Michelle Obama this is for you," he said.
But that wasn't the end of Blunt's cheeky jokes. While introducing "Bonfire Heart," he claimed it was Harry's "favorite song."
"He's a massive James Blunt fan that's why he shipped me out here, and if you're just tuning into ESPN, I'm going to play for the next four hours," Blunt joked.