Why did the demands of the british change by december of 1814?

Britain was facing dissension at home and in Europe by this time. The British Naval force was unable to gain dominance over the Great Lakes, and the British Army was unsuccessful in seizing substantial territory in the United States. The British had spent 10 million pounds in their war against the Americans and the United States was almost bankrupt. By Christmas Eve of 1814, both sides had decided to end all hostilities. All territories and possessions taken by either party during the war were to be returned to their original owners.

In general, history is the recorded story of the interaction between "ideas" "people" and "patterns", since it is the way in which people act and make decisions that influences their collective history.