Super-sub Mario Gotze spectacularly secured Germany their fourth World Cup victory and denied Lionel Messi and Argentina their moment at the Maracana.
Gotze's brilliant finish - just seven minutes before the game would have been decided by the lottery of penalties - settled a nervy encounter in Rio in which chances were at a premium.
It was a record-equalling 171st goal of a storied and memorable tournament - and none were more valuable or better timed.
It's the first World Cup victory for the unified Germany, whose previous wins in 1954, 1974 and 1990 came as West Germany.
And they are the first European team to win football's biggest prize in the Americas – a feat many football experts thought highly unlikely.
Germany were due to be unchanged from the team that humiliated Brazil in the semi-finals until Sami Khedira picked up a calf injury during the warm-up and was replaced by Christoph Kramer.
And considering they had a day's extra preparation - and their final four match was virtually wrapped up in 30 minutes - they had the better of the early exchanges, with Philipp Lahm, Miroslav Klose and Thomas Muller all causing headaches.
However, Argentina's Gonzalo Higuain should have broken the deadlock but spurned a gilt-edged 22nd minute chance with a horror finish that will now long haunt him.
Toni Kroos mistimed a header back to his keeper and Napoli striker Higuain pounced, racing clean through on goal only to inexplicably drag his shot wide.
And it got worse for him seven minutes later, the Argentine striker reeling away to celebrate after sweeping home a Ezequiel Lavezzi cross - only to discover the linesmen's flag had been raised.
Messi finally started to muscle his way into proceedings while Germany's Andre Schurrle - a substitute for late replacement Kramer - should have done better but saw his effort well saved by Sergio Romero.
However, Germany should have seized the lead on the stroke of half-time, Benedikt Howedes smashing a header against the post from close range with Romero totally flat-footed and totally unbeaten.
Messi continued to make his presence felt straight after the interval, brilliantly beating the off side trap and Germany keeper Manuel Neuer, only to see his shot sail a fraction wide of the post with an chance he should have converted. It was to be as good as it got for the player of the tournament.
But the match remained evenly balanced with both sides largely disciplined in defence and positive in attack.
German coach Joachim Low showed virtually no signs of pressure while opposite number Alejandro Sabella lived every pass and tackle, as the game became increasingly nervy, with referee Nicola Rizzoli waving a flurry of cautions.
However, Messi was starting to drift out of the game as the quality took a turn for the worse the more the clock ran down, with just three shots on target - all from Germany - during regulation time.
Both teams were forced into some frantic defending in the closing minutes as the match edged ever closer to extra-time, the third straight World Cup Final not to be settled in 90 minutes.
Low delivered a typically laid-back team talk at the final whistle but whatever he said re-galvanised his troops, as just 38 seconds after the restart Schurrle burst into the box and lashed a powerful shot straight at Romero.
Sergio Aguero was lucky to stay on the pitch as he caught Bastian Schweinsteiger with a swinging arm and yet didn't receive a caution.
But within minutes Gotze had decisively broken the deadlock, flashing a volley past a helpless Romero following Schurrle's precision delivery.
And when Messi lashed over a late free kick in the dying seconds, it was game over – Argentina paying the price for failing to have a single shot on target in 120 minutes.
