The plains contain rich farmland, but doesn't provide any natural barriers to the west
It's timber that has been reclaimed! Reclaimed means salvaged and reused. Ever heard of a dictionary (try cambridge dictionary online)?
If its been properly reclaimed, usually.
Thailand
Polders are found in North European Lowlands.
Netherlands
In 1792, Holland's farmland was characterized by a patchwork of small fields and meadows, often delineated by ditches and hedgerows. The landscape was shaped by a system of polders, where land had been reclaimed from the sea and was carefully managed for agriculture. Crops such as grains, vegetables, and flowers were cultivated, reflecting the agrarian lifestyle of the time. Livestock, particularly dairy cows, were also common, contributing to the region's dairy industry.
Dubai has been building reclaimed Islands. *Reclaimed Islands are Islands that are artifficially created.
Britain
Sweden has been at peace the longest as it has not been involved in a war since 1814.
There have been numerous European dictatorships. Please resubmit the question specifying the country and time-period for a useful answer.
Fertilizer and pesticides