 Ashton said the defeat by South Africa helped England |
England beat France 14-9 in Saturday's semi-final and now have the chance to become the first country to win back-to-back World Cups.
"The players have come so far on a very difficult journey," said Ashton.
"I can't imagine they will be satisfied with reaching the final. They will want to create history."
England's achievement comes after being beaten 36-0 in the group stages by South Africa, who will play Argentina in Sunday's second semi-final.
And Ashton cited that early group game as the turning point in his team's fortunes.
"The South Africa game came at the right time because it gave us a massive kick up the backside and a wake-up call to make sure we got our act together.
"In many ways, that was the defining moment of the tournament for me.
"Since then we have won four games on the bounce and, hopefully, we will make it five next week."
Ashton said the experience within the England camp was crucial to their success so far and suggested their exploits had come as a bit of a surprise.
"We've got the players who know how to win a game," he said. "We have got the armoury within the side to get us in positions where we know we can win it.
"I think that was the big advantage we had over the French team.
"I'd be a liar if you'd have asked me that question five weeks ago - are you going to get to the World Cup final? I would have had to think deep and hard before I said 'yes'.
"But then again hindsight is a wonderful thing. You pick a squad to do a job and this squad was specifically selected to defend the World Cup and that is exactly what they are doing.
"Now that they are in the position they are in, it wouldn't surprise me if they completed the job."
The tense victory over France saw England score a try in the opening exchanges before falling four points behind just after half-time.
But they got over the finishing line thanks to the kicking of fly-half Jonny Wilkinson.
Phil Vickery captained the side and Ashton praised his skipper for helping the team raise themselves for the game.
"Phil is by nature a fairly quietly-spoken person," explained Ashton. "But for a prop forward he thinks pretty deeply about what he is going to say and always comes up with the right thing.
"He made a very moving speech to the team on Friday at seven o'clock, only for five minutes.
"It was about what it meant to him and what it should mean to everyone in the room about playing in a World Cup semi-final and beating France on their home ground.
"I can only assume with the performance that it had some sort of effect.
"From my point of view, and from the way I deal as a coach with the team, he is my ideal sort of captain."
Sir Clive Woodward was coach when England beat Australia to win the tournament four years ago and echoed Ashton's view about experience being the key to their success this time around.
"When you are playing under pressure you want experience," he told 5Live's Sportsweek.
"That's what England have got and is one of the big secrets of this World Cup so far.
"I would definitely keep the same team (for the final). You have got a real momentum going now and whoever they play will be very worried about the England team."
