First year

Voting from Abroad:The International IDEA Handbook, page 41

In the United Kingdom (UK), the political demand for a voice for thosedoing the fighting led in 1918 to the introduction of absentee voting formilitary personnel, conducted by proxy.

http://www.idea.int/publications/voting_from_abroad/upload/chap2.pdf

Armed Forces voting,Standard Note: SN/PC/4276, page 3

For the immediate post war period servicemen overseas were to beentitled to vote by post, and permanent arrangements were made for proxy votingby servicemen.

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In 1920 after some agitation, the Government decided to abandon thepostal voting provisions laid down in the Act of 1918.

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The Representation of the People (No2) Act 1920 provided that postalvoting should be limited to the United Kingdom; servicemen abroad could appointproxies who would be able to vote for them on their behalf.