The televised clash in front of a bumper Coral Windows Stadium crowd looked to be going the way of ten-man Leeds following Matt Smith's 82nd minute opener, but goals from Billy Knott and James Hanson shortly afterwards decisively swung the tie back in the Bantams' favour, sending the home fans into raptures as a result.
Parkinson said: "Without a doubt this is a big moment, we knew what this meant to the people of Bradford tonight (Wednesday) and we said that to the lads before we went out there.
"We knew how we wanted to play but it was very important to come off the pitch knowing we'd given everything, and created a little bit of history. We knew we'd not beaten Leeds at Valley Parade for over 80 years.
"Those fans have gone away tonight knowing we did everything to make that happen for them.
"We have had some good chances before they scored and their 'keeper has had to pull off some decent saves.
"It is never easy when the opposition go down to ten men and they sit back and make it tough. I felt we were patient, however, and we managed to create those chances.
"We couldn't quite get that first goal and got hit by a sucker-punch ourselves, but the response was top class.
"We've tried to play our football in the right way still and we've managed to hit back almost straight away with two goals.
"It took a moment of inspiration from Billy (Knott) to get us back in it. It was a top class finish - similar to the one he scored at Crawley the other week.
"I think the Bradford City fans will remember him for that for quite a while now.
"It was a great cross from Lids (Gary Liddle) for the winner and James Hanson was there to claim the headlines with the header.
"We know here at Bradford that you have to keep going until the final whistle, whether it be in the 90th, 94th or 99th minute of the match.
"I am so pleased for the players and for the Bradford City supporters who have waited a long time to see us beat our local rivals.
"The place was electric tonight - the atmosphere was awesome."