The win is Australia's third in a row of the tour, seeing them overturn a 2-0 series deficit.
"We were more courageous than them in the pressure situations in Australia", he said.
The fifth ODI served as a high-stakes series decider which the tourists won by 35 runs, but it was also the culmination of some four months of hard work for Langer and many members of the team. "Being down 2-0 it would have been easy to roll over".
India's chase looked in good shape early on as they kept pace with Australia's scoring rate, the sides separated by one run at the 15-over mark.
Opener Usman Khawaja hit his second hundred in three matches to guide Australia to 272-9 from their 50 overs. India have been playing non-stop cricket since the fag end of the a year ago when they toured Australia, New Zealand.
The departure of Virat Kohli proved key - as it often does - as Marcus Stoinis got some extra bounce to remove the India captain, who top-edged to Alex Carey for 20.
Usman Khawaja hit a second ODI century of the tour of India
They slipped from 175-1 to 182-4, before Jhye Richardson and Cummins helped them to a score of 279.
Director General Major General Asif Ghafoor on Wednesday took a jibe at India while congratulating Pakistan-born Australian batsman Usman Khawaja for his match-winning performance against the Indian cricket team.
Langer wouldn't be drawn on what the result would mean regarding the World Cup but made it clear the 3-2 series win on the sub-continent carried plenty of importance for a range of reasons.
Now Kohli wants to see his boys having fun in the IPL where they will split up and represent their respective franchises before the next national assignment in the form of the ICC mega event.
The 12-month bans handed down to Smith and Warner by Cricket Australia for their role in the Cape Town ball-tampering incident end on March 28 and the duo are expected to play in the Indian Premier League (IPL) before the World Cup starting May 30.
This win would be a great confidence boost for Australia before heading off to UAE for their final series before the World Cup.