David Silva and Jordi Alba put the holders 2-0 up before half-time and after Italy were left a man short due to an injury to Thiago Motta, Spain cruised to victory with further goals from Fernando Torres and Juan Mata.
Casillas himself broke a European Championship record by extending his run without conceding a goal in the competition to 510 minutes and he is delighted to have been a part of Spanish football's golden era.
He told the Spanish Football Federation website: "This is due to the talent that we all have and the work that people don't see - the work of the past, with everyone in the academies, and the manager who has given this generational change.
"We are living in the most marvellous moment in Spanish football history.
"We have been superior thanks to the work of our players and our characteristics. With Alba's goal we almost sealed it but the third killed it off completely."
The Real Madrid goalkeeper also hopes that success on the football field can bring some happiness to those suffering in the difficult economic times currently afflicting Spain.
"I suppose the people will be happy," he said. "They were before and now even more so.
"We have made the difficult look easy. They will think it has been a walk in the park but we could have been put out in the semi-finals. We have grown, we have gone from strength to strength and we were better.
"We have to enjoy this moment with all those that have suffered. We have lived four unforgettable years."
La Roja coach Vicente del Bosque labelled his side's record-breaking performance in Kiev tonight as "extraordinary".
"It's true we were lucky enough to play a great match," said Del Bosque.
"Everything worked for us.
"It was an extraordinary performance against a difficult opponent."
The manner of the triumph was the perfect answer to a growing number of critics, who have labelled Spain boring, though Del Bosque insisted there was no outside influence involved in Spain's success.
"We played our own game," he said.
"There were no real external influences: we were faithful to what we've done in recent years."
Del Bosque expressed some sympathy for Italy, who had less preparation time after Thursday's semi-final win over Germany.
"The Italians have played a great tournament," said Del Bosque.
"They had the bad luck of the injury to Thiago Motta and that's where it all ended for them, unfortunately."
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