Why the flag should be called "Jack" at all has been the subject of much controversy. It is ordinarily suggested that the derivation is from Jacques, the French word for James, the Union Jack springing into existence under his auspices. Why it should be given this French name does not seem very clear, except that many of the terms used in blazonry are French in their origin. It never seems to have been suggested that, granting the reference to King James, the Latin Jacobus would be a more appropriate explanation, as the Latin names of our kings have for centuries supplanted the earlier Norman-French on their coins, seals, and documents. Several other theories have been broached, of varying degrees of improbability; one of these deriving it from the word "jaque"[35] (hence our modern jacket), the surcoat worn over the armour in mediæval days. This, we have seen, had the Cross of St. George always represented on it; but there is no proof that the jaque was ever worn with the union of the two crosses upon it, so that the derivation breaks down just at the critical point. The present flag came into existence in the reign of King George, but no one ever dreams on this account, or any other, of calling it the Union George.
On the death of Charles I., the partnership between England and Scotland was dissolved, and the Union Flag, Fig. 73, therefore, was disestablished, and was only restored in the general Restoration, when the Commonwealth and Protectorate had run their course, and Charles II. ascended the throne of his forefathers.
The earliest Commonwealth Flag was a simple reversion to the Cross of St. George, Fig. 91. At a meeting of the Council of State, held on February 22nd, 1648-49, it was "ordered that the ships at sea in service of the State shall onely beare the red Crosse { 49} in a white flag. That the engravings upon the Sterne of ye ships shall be the Armes of England and Ireland in two Scutcheons, as is used in the Seals, and that a warrant be issued to ye Commissioners of ye Navy to see it put in execution with all speed." The communication thus ordered to be made to the Commissioners was in form a letter from the President of the Council as follows:--"To ye Commissioners of ye Navy.--Gentlemen,--There hath beene a report made to the Councell by Sir Henry Mildmay of your desire to be informed what is to be borne in the flaggs of those Ships that are in the Service of the State, and what to be upon the Sterne in lieu of the Armes formerly thus engraven. Upon the consideration of the Councell whereof, the Councell have resolved that they shall beare the Red Crosse only in a white flagg, quite through the flagg. And that upon the Sterne of the Shipps there shall be the Red Crosse in one Escotcheon, and the Harpe in one other, being the Armes of England and Ireland, both Escotcheons joyned according to the pattern herewith sent unto you. And you are to take care that these Flaggs may be provided with all expedition for the Shipps for the Summer Guard, and that these engraveings may also be altered according to this direction with all possible expedition.--Signed in ye name and by order of ye Councell of State appointed by Authority of Parliament.--Ol. Cromwell, Derby House, February 23rd, 1648."