'How the Union Jack was made', 1905. The origins of the British flag, showing St George's cross, (England); St Andrew's cross, (Scotland); St Patrick's cross, Ireland; the combined Union flag of England and Scotland, and the Union Jack in the centre. Great Britain was created by the Act of Union between Scotland and England in 1707. The Union Flag dates from 1 January 1801. The Act of Union (1800) merged the Kingdom of Ireland and the Kingdom of Great Britain to form the United Kingdom of Great Britain and Ireland. Illustration from Our Island Story by H E Marshall, published by T C & E C Jack Ltd, (London and Edinburgh, 1905). The book gave a very biased and pro-British view of history.