This proclamation was repeated in January 1630 as John Flower noted: 'there is a commission on foot to call up and compound with such as at the coronation should have come and been fined for not being made knights. Some think the composition will amount to as much as a subsidy'. The practice goes back to medieval times when a landowner could pay a fine in lieu of accepting the obligations of knight service i.e. military service. 
There is a misunderstanding about how Sir William Brockman actually became a Knight. It is quoted in numerous texts that this was because of his devotion to King Charles I and his actions in trying to defend Maidstone in Kent from Oliver Cromwell’s forces (aka the ‘Roundheads’). This is not true. Sir William Brockman was knighted in 1632 and the failed defence of Maidstone occured in the second English Civil War on 1 June 1648. To read Gen. Fairfax's account of the battle click here
Sir William Brockman's Life, Knighthood & Imprisonment
One of our research team Giles Drake-Brockman, received advice from Sue Petrie that the more likely reason for Sir William being knighted was to raise revenue for King Charles 1. Sue states… ‘I think an important point needs to be made about knighthood under Charles I. I hate to disillusion you but knighthood was not about reward but about increasing royal revenue! Kevin Sharpe goes into the practice in great detail in his book The Personal Rule of Charles I, pp.112-116. Landowners worth a certain sum (£40 in land) were liable to present themselves for knighthood (typically at the time of the coronation).
By the end of June 1630 the compositions totalled £11,767. In the localities JPs and deputy lieutenants acted as commissioners and were given the task of ascertaining who was liable for the fines and the amounts they should pay. Most in Kent compounded at the rate of £10. There were of course non-compounders (Sir William?) and the king's attorney was instructed to proceed against sheriffs who impeded the service by 'partial and negligent returns'. So if Sir William compounded for his knighthood in 1632 he had been perhaps 'dragging his feet' over paying up.
So it seems, Sir William Brockman had to purchase his knighthood as part of a revenue raising strategy by Charles I and was not appointed a Knight as a reward for the military actions he undertook defending Maidstone on behalf of his King. This can be verified further because when he was arrested and imprisoned by parliamentary forces in 1632, he is referred to as 'Sir' William Brockman in documents and other letters. Giles Drake-Brockman reviewed  the Brockman Papers in the British Library in 2011 and has since compiled a paper containing 25 letters concerning Sir William's imprisonment. click here
To read a historical overview of Sir William Brockman's life see another paper written by Giles Drake-Brockman click here
"Esse Quam Videri" - To be rather than to seem to be
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