Arf.
When Army officers are promoted, their promotions are listed in a publication called the "London Gazette" (it is legally assumed that items published in the Gazette, which also covers a lot of other official info, are factually correct). In 1954 the Gazette printed one officer's promotion as dating from 1054 and the cheeky bugger applied for back pay. The War Office (predecessor of the MoD) wrote back that it appeared he was due for £39,999, 18 shillings and 5 pence. The letter went on:
"I am directed to invite your attention to para.764 of King's Regulations of that date (21.6.1954) in which it is provided that officers in command of troops shall be held personally liable for the loss of arms and equipment.
On the information contained in in your application you are the sole surviving officer of the Battle of Hastings. Records department informs us that at the battle the English lost 20,000 men valued at £2 apiece."
Then came the final thrust:
"Your account is therefore debited to the amount of 1 shilling and 7 pence."