The purpose of the poster was to express the importance of the alliance between the united states and Britain.
Britain's Day came just after the war ended in December 1918. It was a celebration of the success of the union between Britain and America. In the poster, America, the male, and Britain (seen as Britannia, a female) are seen to be locking hands side by side in a celebration.
This type of cooperation was not the first since they had a previous one where Britain borrowed from American Banks. The union between the two countries is usually the Anglo-American union.
Your question is not complete, the full question should be:
What is the primary purpose of this poster?
SIDE BY SIDE-
BRITANNIA!
Britain's Day Dec.7, 1918
MASS MEETING
a)to express the importance of the alliance between the united states and Britain
b) to encourage people to join the armed forces
c) to convince people to support the arts during wartime
d)to celebrate the victory at the end of the war
To read more about the Britain-American union visit:
brainly.com/question/2653039
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