The Royal Oak In 1651, when King Charles of Scotland, son of the recently executed Charles I, and his army met Oliver Cromwell’s troops at Worcester, they were soon on the run. With Cromwell’s men on their heels, Charles Giffard, King Charles's adviser, knew that they had to move fast. A reward of £1,000, a vast sum of money, had been offered for the king’s capture, so Giffard disguised the monarch as a woodsman.
Samuel Pepys later wrote: “[Giffard] told me . . . that he knew but one way how to pass the next day, and that was to get up into the great oak, in a pretty plain place where we might see round about us, for the enemy would certainly search at the wood for people that had made their escape. . . While we were in this tree we saw soldiers going up and down in the thicket of the wood, searching for persons escaped.”
It took another six weeks before the young king was finally smuggled to safety in France. He finally returned to London on May 29, 1660. In 1664 this day was made a national holiday to mark the Restoration and was officially called “Oak Apple Day” in honour of the oak tree that had protected the king from certain death.
It was surprise to me to find out the history behind the innumerable amount of the Royal Oaks here in the UK. Rest of "The stories behind Britain's pub names" also worth some attention.