The Irish broke two records during the astounding three-wicket win, securing the tournament's highest ever run-chase while Kevin O'Brien clocked up its fastest ever hundred.
He reached his century during the match in Bangalore, India, from just 50 balls, helping towards his team's first ever World Cup victory over England.
O'Brien, who plays for Railway Union club in Dublin, told Sky Sports: "I'm pretty speechless at the moment.
"To be honest it's the best innings I've ever played since I started playing cricket. I just kept going and kept believing and it went our way.
"When we were 111 for five we could have just pottered around, but I chanced my arm and we didn't look back really. We attacked and it came off."
Ireland's prospects of pulling off the victory under floodlights had appeared decidedly slim - particularly after losing captain Will Porterfield to the first ball of their reply.
He hailed the victory as the side's greatest ever win.
"It's got to be the greatest, pretty much the greatest days of our lives so far," he said.
"Credit to the lads, they kept believing. We'll be looking to put in a performance like that every game."
One of Ireland's team, Ed Joyce, has previously played for England but had been deemed surplus to requirements.
England had scored 327 for the loss of eight wickets and captain Andrew Strauss admitted his side had to improve.
"We thought we had done a reasonable job with the bat, we got Ireland five down and things looked comfortable," he said.
"We weren't reckoning on an outstanding innings from Kevin O'Brien. It was pretty brutal."
He reached his century during the match in Bangalore, India, from just 50 balls, helping towards his team's first ever World Cup victory over England.
O'Brien, who plays for Railway Union club in Dublin, told Sky Sports: "I'm pretty speechless at the moment.
"To be honest it's the best innings I've ever played since I started playing cricket. I just kept going and kept believing and it went our way.
"When we were 111 for five we could have just pottered around, but I chanced my arm and we didn't look back really. We attacked and it came off."
Ireland's prospects of pulling off the victory under floodlights had appeared decidedly slim - particularly after losing captain Will Porterfield to the first ball of their reply.
He hailed the victory as the side's greatest ever win.
"It's got to be the greatest, pretty much the greatest days of our lives so far," he said.
"Credit to the lads, they kept believing. We'll be looking to put in a performance like that every game."
One of Ireland's team, Ed Joyce, has previously played for England but had been deemed surplus to requirements.
England had scored 327 for the loss of eight wickets and captain Andrew Strauss admitted his side had to improve.
"We thought we had done a reasonable job with the bat, we got Ireland five down and things looked comfortable," he said.
"We weren't reckoning on an outstanding innings from Kevin O'Brien. It was pretty brutal."
