Prince Harry Opens the Invictus Games

First lady Michelle Obama introduces the royal.

— -- An idea that Britain’s Prince Harry has said he stole from America and “made it bigger” kicked off Wednesday night with his emotional speech in front of thousands of wounded veterans and members of the royal family, minus Duchess Kate.

“Over the next four days, we will see some truly remarkable achievements,” Harry said.

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For Prince Harry, the kickoff to the Games marked the culmination of a yearlong journey that began with a trip to Colorado in 2013 to participate in the U.S. version, called the Warrior Games.

“The Americans made it, I stole it and we made it bigger,” Harry said earlier this week as he handed out the first medals of the Invictus Games for a driving challenge, according to the BBC.

One-quarter of the 400 participants in the Invictus Games are U.S. veterans. Prince Harry has already met with some of the U.S. competitors who flew into London to compete.

“I’ve realized what a difference it can make, using the position to do good,” Harry said of his high-profile role in putting the Games together.

The athletes gathered in London will compete in adaptive sports ranging from wheelchair rugby and basketball to archery and indoor rowing, according to the Invictus Games' website.

The Games' official anthem was penned by Coldplay's Chris Martin and performed Wednesday by singer's from the U.K.'s Armed Forces.