Gautam Gambhir and Mahendra Singh Dhoni guided India to World Cup glory on home soil, chasing down a target of 275 under floodlights in Mumbai for a six-wicket win over Sri Lanka.
Sri Lanka had appeared in excellent shape after Mahela Jayawardene's 103 not out from 88 balls underpinned a total of 274-6 at the Wankhede Stadium.
Lasith Malinga removed Virender Sehwag and local hero Sachin Tendulkar to reduce India to 31-2 in reply, before Gambhir took control of proceedings.
The left-hander shared stands worth 83 with Virat Kohli (35) and 109 alongside Dhoni to turn the tide in the hosts' favour.
He missed out on a century, bowled for 97 after advancing to Thisara Perera, but a perfectly paced run chase was completed in the penultimate over by a huge six from Dhoni, who finished on 91 not out.
India's triumph ended a 28-year wait to add a second World Cup victory to their inaugural success in 1983, while Sri Lanka, the winners in 1996, have now lost in the last two finals.
Sri Lanka, who surprisingly dropped Ajantha Mendis among four changes to their starting XI, were earlier indebted to a masterful 14th one-day international ton from Jayawardene to ensure a decent total.
The day had begun in somewhat strange circumstances; match referee Jeff Crowe allowing a re-toss after nobody - apart from, presumably, the man himself - was quite sure what Kumar Sangakkara called the first time around.
The Sri Lanka captain got it right at the second attempt and had no hestiation in batting first on a bare pitch that looked full of runs.
Zaheer Khan, however, opened proceedings with three consecutive maidens and, with the first delivery of his fourth over - the seventh of the innings - had Upul Tharanga caught by Virender Sehwag at slip.
Tharanga's contribution of two off 20 balls was not exactly the start his side had in mind, but Tillakaratne Dilshan and Sangakkara restored order during a second-wicket alliance of 43.
Dilshan's promising innings was terminated at 33 in unfortunate circumstances in the 17th over when an attempt to sweep Harbhajan Singh deflected onto his stumps via a combination of glove and leg.
That brought together Sangakkara and Jayawardene - Sri Lanka's middle-order engine room throughout the last decade - and once again they mixed sharp running with the occasional boundary in a 62-run stand.
It was something of a surprise when Sangakkara edged behind attempting to cut a short ball from Yuvraj Singh's left-arm spin.
The skipper's departure reduced Sri Lanka to 122-3 in the 28th over and was the start of a fightback in the field by India as Jayawardene, having brought up his half-century from 49 balls, lost Thilan Samaraweera and Chamara Kapugedera in consecutive overs.
Samaraweera was lbw to the golden arm of Yuvraj and Kapugedera, making only his second appearance of the tournament, chipped Zaheer's slower delivery straight to Suresh Raina in the covers.
Needing an ally, Jayawardene found one in Nuwan Kulasekara and the sixth-wicket pair upped the tempo, helped by their decision to save the batting power play for the final five overs.
Jayawardene went to three figures with consecutive boundaries off Zaheer in the 48th over, which concluded with the run out of Kulasekara as he tried to steal one to the wicketkeeper.
Perera ensured the innings finished with a flourish, belting a six and three fours in a nine-ball 22 as Zaheer's final two overs disappeared for 35 to ruin his figures (2-60).
India's pursuit had begun badly, as Malinga removed Sehwag for a duck with the second ball and followed up with the prize scalp of Tendulkar later in his opening spell.
Sehwag was lbw trying to work a straight delivery into the leg-side, a fact confirmed by a DRS review, and Tendulkar (18), having hit a couple of early boundaries to raise hopes of a fairytale 100th international hundred in his home city, edged a drive low to wicketkeeper Sangakkara.
Gambhir and Kohli stabilised the run chase with an 83-run partnership in 15.3 overs, Gambhir surviving on 30 when Kulasekara failed to hold a tumbling chance at long-off in the first over of spin from Suraj Randiv.
Kohli did fall to spin, albeit of the part-time variety, as Dilshan accepted a difficult return catch.
With 161 needed off 170 balls, India captain Dhoni promoted himself and set about the task with relish.
Both Gambhir and Dhoni advanced to half-centuries and had reduced the equation to 52 required from 53 when Gambhir suffered a rush of blood against Perera to deny himself a century.
Dhoni and Yuvraj always retained control and, with the batting power play used for the final five overs, were able to complete the job with 10 balls to spare.
Sri Lanka spinner Muttiah Muralitharan's final international appearance ended in disappointment as the leading wicket taker in Test and ODI history, patently unfit, finished with figures of 0-39 from eight overs.