Young star Ryan Semple set Mark Wright's men on their way to a long overdue home success as they shook an unwanted monkey from their backs.
The homegrown winger scored his second senior goal in as many matches to break the deadlock five minutes before the break and end the unease around London Road.
Posh went into this fixture in possession of the worst home record in League Two. In eight previous matches, they had scored just seven goals and collected only nine points.
But they were always in control of this contest against a below-par County side and Semple gave them a timely advantage.
He pounced to bundle the ball over the line from point-blank range after the hosts had twice been thwarted by the woodwork in the same attack.
A wicked left-wing free-kick from recalled defender Peter Kennedy sparked a bout of panic in the County defence. Sean St Ledger saw his shot on the turn rebound off an upright before captain Dean Holden's follow-up was deflected against the crossbar by keeper Kevin Pilkington.
But he was powerless to stop Semple reacting quickest to smuggle the ball across the line and Pilkington was at fault as Posh doubled their lead 12 minutes into the second period.
The one-time Manchester United man dashed 30 yards from his line in pursuit of a long pass from Mark Arber.
But he was beaten to the ball by rapid home striker Calum Willock who lobbed into the empty net with tremendous aplomb to score for the third time this season.
The former Fulham frontman has been beset by injury problems during two years at London Road, but he is expected be a prolific figure in an anticipated Posh push for a play-off place.
Willock's strike partner Danny Crow was another player denied by the woodwork, while home keeper Mark Tyler was only required to make one noteworthy save when keeping out a Lewis McMahon drive midway through the second half.