It is hard to believe that the flag of St David has only been known in Wales for the last couple of decades, There is a large one along the ceiling in St Davids Cathedral with the cinquefoils thereon but hardly any others were seen prior to 1994. 

The Welsh Tartan Company were looking around for a 'brand' to complete the Brithwe Dewi Sant (St David's Tartan)  John Wake, then of the WTC, set out to look for an emblem that could be used commercially or indeed patriotically across Wales on their merchandise. The feeling at the time was that the Union flag did not contain any Welshness, the cross of St George representing Wales as a principality of England. 

The Dean of St David's told Wake that the cinquefoil and the cross were their property and advised help from a London royal official office.

Wake surprisingly was then told the Prince of Wales probably owned the rights to the flag and may not give permission. There was neither outright animosity to the flag being produced and used, nor any enthusiasm. It was decided, after a lawyer was consulted, that the flag could be used as long as there were no cinquefoils on it. A thousand flags were produced without the cinquefoils; they were distributed around Wales and a  PR campaign took place to increase knowledge of the St David's flag. It was ironic to think that even the strongest Welsh speaking areas of Wales were unaware of the the emblem. 

The flags were hung prominently in the Welsh shop in the centre of Cardiff and at other locations. Wake even spoke to the then chief Executive of Cardiff City Football Club who went  with him to the woollen mill at Llanwrtyd Wells to discuss tartans and emblems. The flag was then incorporated into the club logo.  This was later dispensed with as new owners took over.   Within 10 years, the St David's Flag was known and flown across Wales in patriotic use. It was never a flag to usurp the Red Dragon but to complement it, and perhaps to get Wales's own Patron Saint's emblem to proudly fly alongside the emblems of the other nations, St George, St Andrew and St Patrick.

The actual origin of the design is lost in the mists of time.  Some say it was as early as 7th century but that is strongly disputed by scholars.  In fact nobody really can give with any proven conviction to the debate. So prior to 1994 it is the Deans of St Davids who had the original design (with cinquefoils) within their remit. After, without the cinquefoils, it belongs to the nation.