This flag with the harp of Ireland and the red cross of England replaced the British Union Flag during during the Interregnum (1649 to 1660) when the royal coat of arms, along with monarchy, was removed from the English flag.
After the English Civil War the Parliament had declared England to be a Commonwealth on May 19, 1649.
The Union Jack was abolished in 1649 after the execution of Charles I, but would be revived as a flag solely for the King's ships in 1660 when the monarchy was restored. The Commonwealth of England had a republican government which ruled first England and Wales (1649-1653), then Ireland and Scotland (1653-1659). The government during 1653 to 1659 is properly called "The Protectorate," and was ruled by the Lord Protector, Oliver Cromwell, with dictatorial powers until his death.
5 feet x 3 feet - Polyester with metal eyelets.