Final answer:
The three-field system was an important agricultural innovation in Northern Europe during the Early Middle Ages, as it improved land use, increased food production, and prevented soil depletion.
Step-by-step explanation:
The three-field system was a significant agricultural innovation developed in Northern Europe during the Early Middle Ages. It involved dividing the arable land into three fields, which were rotated each year. This system allowed for more efficient use of the land, increased food production, and reduced the risk of soil depletion.
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