Colback made the bold switch from Wearside to St James' Park in June in after his Sunderland contract expired, ending a 15-year spell at a club he joined aged 10.
The 24-year-old was handed his first international call-up on Thursday and Newcastle boss Pardew is in no doubt that the midfielder may have been overlooked by Roy Hodgson had he not shown the character turn his back on Sunderland to join their arch-rivals.
"It's great for north-east football, because he did a lot of this [to earn his] call-up at Sunderland," Pardew said.
"I think he's ticked a couple of boxes here, though, that are important for an England manager.
"One, he has moved to a local rivals and he has handled it well; and then he has come into our team and played well, and that has ticked another box for the England manager.
"When you go to England, you have to show that you have got a personality to deal with all the pressure that comes with playing for England.
"There's the extra media spotlight, the extra spotlight of analysts and the experts in the studio, and I think the move to us underlined the fact that he can deal with that."
England play Norway in a friendly at Wembley on Wednesday before starting their Euro 2016 qualification campaign against Switzerland in Basel on September 8.