November 27 has been Lancashire Day since 1996 when it was belatedly created to commemorate the day in 1295 when Lancashire sent its first representatives to Parliament.
As an act of unity, and no matter where they are in the world, Lancastrians are asked to raise their glasses at 9pm GMT and drink the Loyal Toast to The Queen, Duke of Lancaster.
When Lancashire was established in 1183, it bordered Cumberland, Westmorland, Yorkshire, and Cheshire.
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Now the modern administrative county is much smaller due to significant local government reform in 1974.
However, Lancashire's physical boundaries have not actually changed since the middle ages.
The Friends of Real Lancashire aims to promote the "true" identity of the county and will present a recently designed flag to the mayors of Preston and Lancaster today.
The new design has been registered by the Flag Institute, meaning Lancastrians can now wave it without planning permission.
It features a red Lancashire rose on a gold background and applies to the whole of "traditional" Lancashire from Liverpool and Manchester in the south, to Barrow-in-Furness and the southern Lake District in the north.
Chris Dawson, Friends of Real Lancashire chairman, said: "We follow Lancashire County Cricket Club which covers the whole of Lancashire and we always cheer on Lancashire teams when they play teams from other parts of the country in football, especially if they are playing a Yorkshire team.
"We have written to Buckingham Palace and we always get a letter back wishing everyone a happy Lancashire Day so we are expecting that to drop through the door any day now.
The Queen is unique to Lancashire because, as well as being the Queen, she is also the Duke of Lancaster."
The Lancashire Day Proclamation "Know ye that this day, November 27th in the year of our Lord 2008, the 57th year of the reign of Her Majesty Queen Elizabeth II, Duke of Lancaster, is Lancashire Day. "Know ye also, and rejoice that, by virtue of Her Majesty's County Palatine of Lancaster, the citizens of the Hundreds of Lonsdale, North and South of the Sands, Amounderness, Leyland, Blackburn, Salford and West Derby are forever entitled to style themselves Lancastrians.
"Throughout the County Palatine, from the Furness Fells to the River Mersey, from the Irish Sea to the Pennines, this day shall ever mark the people's pleasure in that excellent distinction – true Lancastrians, proud of the Red Rose and loyal to our Sovereign Duke. "God Bless Lancashire and God save the Queen, Duke of Lancaster."