Quote Originally Posted by MacMillan of Rathdown View Post
Actually, Mr. Phillips declined the offer of a title (earl) and it was at the express request of HRH The Princess Royal that no titles were granted to her children. But you're right, they are untitled nobles.
Titles and Princely status are two separate issues here. In Letter's Patent dated 30 November 1917, the King (George V) restricted the style Royal Highness and the titular dignity of Prince or Princess of Great Britain and Ireland to the children of the Sovereign, the children of the sons of the Sovereign, and the eldest living son of the eldest living son of a Prince of Wales. Anne therefore qualifies but her children do not. Strictly speaking she was not actually entitled to the style of Princess until her mother became the Sovereign being the granddaughter through the female line of George VI and neither did her brother. HM was always heir presumptive and never heir apparent due to the male preference primogeniture system.

Quote Originally Posted by MacMillan of Rathdown View Post
Who is, and more importantly who is not, a member of the Royal family is determined by Her Majesty, and by Her Majesty, alone (within the confines of the act of settlement). Likewise Her Majesty, as the font of all honours, may ennoble-- or degrade-- an individual in their title by her own mere motion. Thus after a divorce a Royal may be deprived of Royal status, and thereby forfeit the right to use HRH in front of their title.
I am not aware that Her Majesty has ever varied the letters patent of her grandfather. Thus one may have non titled members of the Royal Family who are in line of succession through the female line. In the male line the letters patent still apply to the children of Charles, Andrew and Edward whose wives status depended upon their marital position as we do not have morganatic arrangements.

Quote Originally Posted by MacMillan of Rathdown View Post
I know what you are driving at, but I think it somewhat misleading when you refer to Her Majesty the Queen Mother as being a commoner prior to her marrying into the Royal Family and thus acquiring royal status. As the daughter of an earl she retained all of the prerogatives of nobility, including the style of "Lady". True, as the daughter of an earl she was eligible to seek elective office and if successful take her seat in the lower house of parliament, but this concession in the electoral laws did not take from her her noble status.
Read any commentary you wish about her status prior to her marriage and you will see the word "commoner" used, including in her official biography by William Shawcross that I happen to be currently reading. Yes, she was still noble at the same time but was still non royal. Hers was the first marriage of a commoner into the Royal Family since Anne Hyde married a previous Duke of York (who became James II & VII). Since that time male royals had had to look to find Princesses to marry. Interestingly I found that she and Prince Albert could claim common descent from Henry VII which made them 13th cousins!

Quote Originally Posted by MacMillan of Rathdown View Post
As nobiliary practice relates to Mr. Mark Phillips and Mr. Anthony Armstrong-Jones, as far as I am aware Mr. Phillip's family was non-armigerous, thus he was not noble, hence he was a commoner by most definitions. Mr. Anthony Armstrong-Jones did come from an armigerous family, and was armigerous himself prior to wedding HRH Princess Margaret, thus he was noble, and most certainly not a commoner. That he was given an earldom (Snowdon) on his wedding day merely elevated him to the status of the titled nobility (and, in my opinion, was a much better wedding present than a new pop-up toaster!). Snowdon's children, by the way, rank 12th and 13th in line for the throne, right after the children of Princess Anne-- that hardly makes them common.
Do not confuse "commoner" with "common." Snowdon's children have the right to the title of Lord and Lady because of him having an Earldom (pop up toaster notwithstanding!) They derive no rank or title through Princess Margaret though they do derive their place in the line of succession from her.