Rose joined the club on loan from last month after being sidelined at Tottenham Hotspur by Jose Mourinho.
The England international needs games ahead of Euro 2020, and it an easy deal to get done, according to Bruce, who also signed Valentino Lazaro and Nabil Bentaleb on loan in the transfer window.
“I think it was common knowledge that things weren’t hunky dory (for Rose) two or three weeks before,” said Bruce, United's head coach.
“You’re always monitoring a situation like that. There’s probably one or two at every club. There’s (Jack) Colback and (Henri) Saivet here, for example.
“You monitor it. What helped enormously was Danny being a northern lad. And he wants to pay. It became very easy. The player was surplus to requirements at Tottenham.
“It wasn’t as difficult as Lazaro, where we have to beat off eight or 10 (clubs). Danny wanted to be here, and that helped. I hope that he’s been one of the better ones of the transfer window, certainly for a club like ours to get England’s left-back, he was until September.”
Rose, signed after Jetro Willems suffered a season-ending injury, was outspoken at times at Tottenham.
“I don’t mind that (his outspokenness) at all,” said Bruce. “He’s fitted in well. He’s trained well and worked hard.”
Rose spoke about the impression Newcastle fans made on him on previous visits to St James’s Park after making his debut.
“I think the big thing for Danny was ‘let’s get the deal done’,” said Bruce. “From our point of view, it was ‘come and play, and let’s see how you enjoy it’. I certainly hope he plays well for us and that he wants to stay.
“I think it helps that he’s from the North. It does become a bit of an issue in terms of getting people here. If people have London or Newcastle, then most of them choose London for whatever reason. I can’t understand that myself, but there you go.
“I think he understands what the club is about.”