Short answers, pulled from the story.
The Order of the British Empire was established on the 4th of June 1917 by King George V. It was created to recognise the many thousands of people across the Empire who had served in non-combat roles during the First World War, filling a gap in the existing honours system that only rewarded royals, senior officers, diplomats, and those who had personally served the royal family.
The five classes, from highest to lowest, are: Knight Grand Cross or Dame Grand Cross (GBE), Knight Commander or Dame Commander (KBE or DBE), Commander (CBE), Officer (OBE), and Member (MBE). The two senior ranks entitle male recipients to the title Sir and female recipients to the title Dame.
John Lennon returned his MBE insignia on the 25th of November 1969 as part of his ongoing peace protests. Despite returning the medal, the honour was never formally annulled and remained officially in place, because only the monarch can revoke an honour on the recommendation of the Honours Forfeiture Committee.
The first investiture took place at Ibrox Stadium in Glasgow, during a royal visit to the shipyards. Alexander Ure, 1st Baron Strathclyde received the first GBE in recognition of his role as chairman of the Scottish War Savings Committee, and Lizzie Robinson, a munitions worker, received the first medal of the order.
The ribbon colour changed in 1937 as part of revisions to commemorate the reign of King George V and Queen Mary. Queen Mary had originally preferred rose pink for the riband when the order was founded in 1917, but purple was chosen instead. After she became Grand Master in 1936, the change was made, and since the 9th of March 1937 the riband has been rose pink edged with pearl grey.
The Order of the British Empire has more than 100,000 living members worldwide, making it by far the largest of all British orders of chivalry. The order is capped at 300 Knights and Dames Grand Cross, 845 Knights and Dames Commander, and 8,960 Commanders, with annual limits applied to Officers and Members.