For a long time, northern Europe was a scientific backwater: new ideas came from other places to northern Europe, and not the other way around. The earliest people came to northern Europe probably about a million years ago. These were not modern people, but earlier almost-humans. From Africa, they brought with them the knowledge of how to make Acheulean stone tools, and the use of fire. These early people kept on making Acheulean stone tools until about 200,000 years ago, when they began to make more efficient Mousterian tools instead.
When the earliest modern humans left Africa and walked to Europe, they arrived about 50,000 BC, bringing with them newer African scientific advances like tame dogs and leather clothing and painting, bows and arrows and fishing.
Indo-European people migrating to Germany from Central Asia about 2000 BC brought with them many more new inventions, like horses and wagons, spinning and weaving, and the composite bow that you could use while you were riding your horse. They also brought domesticated pigs and cattle with them.
Reproduction of a press from Gutenberg's time
With the rise of the Roman Empire, the Romans (also Indo-Europeans) began to exchange ideas with their new subjects in West Asia and Egypt, and brought back new things to trade with the Germans to their north - wine, and wheel-made pottery, and iron tools. Under Roman rule, Cologne in northern Germany became a center of the new industry of glass-blowing.
But it was not until after the fall of the Roman Empire, in the Middle Ages, that northern European scientists really began to make their own original contributions to the world. Somebody invented the harrow, which allowed farmers to plow and plant heavier soils more efficiently. The harrow encouraged a lot of people to move to northern Europe, and made Europeans richer, so they could educate and support more scientists. Thanks to the communications encouraged by the huge Mongol Empire, northern European scientists learned about paper, printing, and distillation in China and the Islamic Empire. The Germans were able to use these new ideas to invent fizzy beer, brandy, and eventually Gutenberg's printing press with movable type.