Put in to bat on a green-topped pitch on the opening day of this Second Division contest, Gloucestershire had the better of things to reach 242-5 before bad light intervened with 10 overs unused.
Joe Denly weighed in with two wickets for Kent, but Western Australia batsman Bancroft took centre stage, registering an authoritative 124 not out from 260 balls and staging an opening stand of 141 with Chris Dent.
First employed by Gloucestershire as a short-term locum for the absent Michael Klinger in 2016, Bancroft was invited back for the whole of this season. But he has struggled to find consistency in English conditions and went into this game having scratched 424 runs at an average of 26.50.
He was fortunate not to be given out in single figures on this occasion, the Australian surviving a strident appeal for lbw from veteran campaigner Darren Stevens in the fourth over of the day.
He certainly made good his escape, chiseling 50 from 125 balls in a patient innings characterised by sound temperament and good technique.
He and Dent raised three figures inside 39 overs and went on to register Gloucestershire’s highest opening stand of the summer against a Kent attack that lacked a cutting edge.
A third hundred of the season appeared to be there for the taking for Dent, who passed up the opportunity when attempting to sweep Denly and departing lbw for 59. Given that the left-hander had already plundered ten runs in the over, it was a needless shot.
But there was no stopping Bancroft, whose second 50 occupied 72 balls as batting became easier. He was especially severe on Denly, hitting him for six and four off consecutive balls in the 54th over to move into the nervous nineties.
When he clipped the same bowler off his legs to attain three figures via 197 balls soon afterwards, a sparse County Ground audience stood to show their appreciation of a fine innings.
Gareth Roderick clipped Mitchell Claydon to short mid-wicket for ten and Academy product James Bracey was dismissed lbw by Denly for 12 in the act of sweeping as Gloucestershire, reduced to 193-3, threatened to squander a position of strength.
Kent made good use of the second new ball, Adam Milne and Stevens removing George Hankins and Phil Mustard respectively, only for Bancroft and Jack Taylor to summon stiff resistance thereafter.
Kent head coach Matt Walker said: “We thought there would be a little bit in the pitch this morning, but it turned out to be a tough day. We applied pressure at times, but overall, we just lacked that little bit of intensity.
“You have to say Gloucestershire batted well and Dent and Bancroft gave them an excellent start. We felt we might have got him out early on, but Bancroft played a fine innings once he got his eye in.
“It’s about reacting in the right way and taking responsibility when things are difficult and I thought the bowlers stuck to their task. They came back well in the final session and put us back in the game.”
Gloucestershire batsman Cameron Bancroft said: “It felt good to show the Bristol crowd what I could do. Things have been a bit frustrating – I’ve had starts and not been able to go on and make that really big score.
“It’s definitely nice to get that first hundred under my belt for Gloucestershire and I enjoyed doing the hard yards and getting the monkey off my back. I’ve been close on a few occasions and not quite been able to get over the line.
“A lot of credit has to go to Chris Dent. he played really well and helped take the pressure off me. We put on 96 for the opening wicket at Leicester last week and it was good to improve on that here. We’ve not done that often enough this season.
“I just love spending time in the middle and scoring runs and I’ll just try to keep going tomorrow and turn it into a real biggie. We’re in a good position, but there is more work still to be done.”