This is an official poster of the Declaration of Arbroath, or to use its other name, the Scottish Declaration of Independence.
It is produced by the Scottish Record Office - national archives.
It is 27 inches(70cm) wide and 39 inches (100cm) high and comes complete with an english translation.

"The Declaration of Arbroath" is one of the best known and most treasured document in the national archives of Scotland. It is a letter from the earls and barons of Scotland to the Pope during the War of Independence, expressing the country's independent national identity and asking him to urge the English king to cease his aggression towards Scotland. It was signed on April the 6th 1320 at Arbroath Abbey. The accompanying leaflet provides a translation by Sir James Fergusson, a former Keeper of the Records of Scotland. For ease of reading, the translation has been arranged into paragraphs, with shorter sentences and modern punctuation.