England were made to work hard to retain their title, losing a two-goal advantage thanks to goals from Nelson Weiper and Paul Nebel, but a 91st-minute header from Jonathan Rowe was enough to see them over the line.
It was Rowe's first goal in the tournament, and Carsley applauded the Marseille striker for taking his chance when it presented itself.
Carsley said to reporters during the post-match press conference: "Jonathan's done so well when he has got an opportunity at Marseille, and he fully deserves to be in the squad.
"He probably thought that he was out of the selection, but he has more than deserved to be part of it. He has started a few games, came on as a sub, made an impact and his enthusiasm around the hotel and training has been infectious."
Germany will look back at the final with some regret, namely that the tournament's top goalscorer, Nico Woltemade, was unable to muster one shot on target in the 120 minutes of play.
Speaking about how he kept the striker quiet, Carsley explained: "The two centre-backs (Jarrell Quansah and Charlie Cresswell) and Alex (Scott) and Elliott (Anderson) should take a lot of credit for that.
"We tried to almost throw a net around him when the ball was near him because we knew how dangerous he was.
"We probably spoke about him for maybe five minutes in total because I always want to think about our threats."
Their success in Slovakia has been built around a lone striker system, headed by Jay Stansfield. In the second half, he was replaced by a more defensive player in Brooke Norton-Cuffy. Rowe, brought on at the start of extra time, made an instant impact in the number nine role with his goal.
Carsley's tactical decision to go strikerless for the last 28 minutes of the game was England's best chance to win the game.
"I always try and keep as many attacking players on the pitch because I wanted to win, I wanted to score. I always think the longer you can keep Harvey (Elliott) and James (McAtee) on, the more chance you have of either creating or scoring a goal.
"In my mind, the substitutions are all about attacking and I don't want this generation of England players to see a game out, I want us to score again, I want us to try and win the game by scoring goals rather than taking them chances of going to penalties or leaving anything to chance.
"They definitely took that on board; every time we attacked, we tried to score."
England's achievements in going back-to-back mirror those of the 1980s when under Dave Sexton, they were able to achieve the same feat.
The tournament has grown since then, and six games in 16 days has been a whirlwind for the side. Carsley attributed the win to his whole squad and their belief in getting the job done, whilst not ruling out the possibility of going for the never-done-before hat-trick in 2027.
He added: "I am not thinking about moving on too quickly. It was a great target to go for Dave Sexton's two in 82 and 84 and the most important thing is that the Under-21s keep winning, keep producing players for the senior team.
"It's a brilliant thing to go for, I am definitely looking forward to that. It's a great target to go for, I don't think it's been done before.
"But, we have to give this squad so much credit. I am so proud of the players."