Early in the reign of King Charles I, William Graham, 7th Earl of Menteith, "having by his talents and eminent services to the State attained a position of commanding influence and power, resolved to reclaim the Earldom of Strathern, of which his progenitor, Malise Graham, first Earl of Menteith, had been unjustly deprived by King James I ... " [Scots Peerage I:133]. The descent is as follows:
Robert II, King of Scots (d. 1390) m2. 1355 Euphemia of Ross David Earl of Strathearn (d. before 1389) m. --- Lindsay Euphemia Countess of Strathearn m. Patrick Graham (d. 1413) Malise Graham 1st Earl of Menteith (d. by 1490) m. Janet de Rochford Patrick Graham m. Isobel Erskine Alexander Graham 2nd Earl of Menteith (d. 1537) m. Margaret Buchanan William Graham 3rd Earl of Menteith (d. 1544) m. Margaret Moubray John Graham 4th Earl of Menteith (d. 1565) m. Marion Seton William Graham 5th Earl of Menteith (d. 1578) m. Margaret Douglas John Graham 6th Earl of Menteith (d. 1598) m. Mary Campbell William Graham 7th Earl of Menteith (d. 1661)
On 25 May 1630, William Graham, 7th Earl of Menteith, was served heir of line to Earl David and Euphemia, Countess of Strathearn, and on 31 July 1631, by Royal Charter, he was confirmed in the dignity of Earl of Strathearn.
As is normal when someone gains power, the Earl had accumulated a number of political enemies. His assumption of this older title, combined with his own misjudgement, allowed his enemies an opportunity. To explain this, we must first examine the reasons for, and some of the consequences of, a 1371 Act of the Edinburgh Parliament.
On 22 February 1371, David II, King of Scots, died, and his nephew, Robert Stewart, High Stewart of Scotland, succeeded as King Robert II. The new King Robert II had married twice, first to Elizabeth Mure, and second to Euphemia of Ross, and had a number of sons and daughters by each wife. In each case, Robert had received a Papal dispensation for his marriage (for the first marriage the dispensation was from Pope Clement VI and was dated 22 November 1347, for the second marriage the dispensation was from Pope Innocent VI and was dated 2 May 1355).
There was a problem, though. The dispensation for Robert's first marriage was not granted until after all of the children by that marriage were born. This meant that there could be some question about the legitimacy of the children by this marriage, and consequently the ability of the children of this marriage to succeed to the Throne.
The Edinburgh Parliament settled this question by passing an Act, on 27 March 1371 [Acta Parl. Scot., i. 549], which left the Throne to:
1. The King's oldest son, John, Earl of Carrick, and the heirs male of his body. The King's second son, Walter, Earl of Fife (j.u.) had already died without issue. 2. The King's third son, Robert, Earl of Menteith, and the heirs male of his body. 3. The King's fourth son Alexander, Earl of Buchan, and the heirs male of his body. 4. The King's fifth son David, Earl of Strathearn, and the heirs male of his body. 5. The King's sixth son Walter, Earl of Atholl, and the heirs male of his body. 6. Upon the extinction of these, the throne was to pass to the heir whomsoever of the King.
The oldest four sons (John, the older Walter, Robert and Alexander) were the King's sons by Elizabeth Mure, and the youngest two sons (David and the younger Walter) were the King's sons by Euphemia of Ross. When King Robert II died on 19 April 1390, he was succeeded under the terms of the 1371 Act by his oldest son John, Earl of Carrick, who took the regnal name Robert III.
For the next century and a half, the Scottish Throne was held by the heirs male of the body of John/Robert III. During that time, the heirs male of the body of Robert Stewart, Earl of Menteith and later Duke of Albany, had presumably become extinct in 1451 (the question of the legitimacy of his great-grandson, Walter Stewart of Morphie, is not discussed here, officially Walter Stewart of Morphie was illegitimate); Alexander Stewart, Earl of Buchan, died without legitimate sons around 1405; David Stewart, Earl of Strathearn, died without sons by 1389; and the heirs male of the body of Walter Stewart, Earl of Atholl, became extinct in 1437.
King James V, the last heir male of the body of John/Robert III, died in 1542 and was succeeded on the Throne by his infant daughter Mary, Queen of Scots. If James V's cousin, John Stewart, Duke of Albany (d. 1536), had lived a few more years, then Duke John would have succeeded to the Throne (as heir male of the body of John/Robert III), rather than Mary (as heir whomsoever of Robert II). Mary, Queen of Scots, is the ancestor of all succeeding Monarchs of Scotland.
It was Mary's grandson, King Charles I, who on 31 July 1631 granted the Royal Charter which confirmed William Graham, 7th Earl of Menteith, in the dignity of Earl of Strathearn, as the heir of line of David Stewart, Earl of Strathearn, oldest son of King Robert II by his second wife, Euphemia of Ross.
At around this time (the early 1630s), the legitimacy of Robert II's children by his first wife Elizabeth Mure was a matter of controversy. One possible consequence of their illegitimacy would be in regards to the succession to the Scottish Throne under the terms of the 1371 Act. After the various sons of Robert II and the respective heirs male of their bodies, the Throne was to pass to the "heir whomsoever" of King Robert II. Could illegitimate children, and descendants of illegitimate children, qualify as an "heir whomsoever"? The eventual answer is that, yes, they can, under certain circumstances. These circumstances are that the parents eventually marry, that the parents had no impediment to their marriage (such as being married to someone else) at the time of the birth of the child, and that both parents are domiciled in Scotland. For some later examples of this doctrine at work, see the 1910 decision in regards to the succession to the Macdonald Baronetcy [S. 1625], and the 1885 decision in regards to the succession to the Lauderdale peerage.
The issue of King Robert II by Elizabeth Mure also conform to these circumstances, so the succession of Mary to the Scottish Throne in 1542 as heir whomsoever of King Robert II would eventually be accepted as established. However, in the early 1630s, this doctrine was not fully settled, which means that there was some question at that time as to whether Mary's succession in 1542 was correct. If the children of King Robert II by his first marriage, and the descendants of these children, were ineligible to be considered his "heir whomsoever" on the grounds of their illegitimacy, and they and their descendants were to be barred from succeeding to the Throne on these grounds, then the heir whomsoever of King Robert II, and, under the terms of the 1371 Act the rightful heir to the Scottish Throne after the extinction of the male-line issue of the sons of King Robert II, must be found among the descendants of the second marriage of King Robert II. This person was the Earl of Menteith. In the early 1630s the then Earl of Menteith was powerful and ambitious and had been served as heir of line to David Earl of Strathearn (the oldest son of the second marriage of King Robert II) and confirmed by Royal Charter in the dignity of Earl of Strathearn [Complete Peerage VIII:673 (g)].
The Earl didn't make it any easier on himself, as he boasted in the presence of witnesses that he had the reddest blood in Scotland and that the King was obligated to him for his throne. Because of this, "King Charles was made to feel that he had acted rashly and imprudently in countenancing Menteith's claim, and severe if not oppressive measures were taken to undo what been done, and to destroy for ever any appearance of pretension on Menteith's part to Royal descent from the Earl of Strathern. His retours of service as heir of line of Prince David and Countess Euphemia were illegally annulled, his patent was cancelled, and he was compelled to accept a new title which should extinguish that of Strathern and make even Menteith a secondary dignity. This was the origin of the Earldom of Airth, the creation of which marked the fall of the former royal favourite" [Scots Peerage I:135].
The charter and the retour were both reduced by the Court of Session on 22 March 1633, and the patent of the Earldom of Airth is dated 21 January 1633 and passed the Great Seal on 28 March 1633.
The Earl of Airth and Menteith was succeeded in his peerages by his grandson, who died without issue in 1694. Because of some convoluted and imprecise language in the 1633 patent, the devolution of the Airth and Menteith peerages after 1694 (the extinction of the heirs male of the body of the 1633 grantee) has never been clear. See, for example, Sir Harris Nicolas, History of the Earldoms of Strathern, Monteith, and Airth . A number of claims to some or all of these peerages have been made over the years by persons who were, or who claimed to be, the heir male whatsoever, the heir of line, and so on, but to date none of these claims have been successful.
The second Earl of Airth and Menteith had two sisters, Lady Mary and Lady Elizabeth, and their seniority has never been established. Nevertheless, the last descendant of Lady Elizabeth died in 1821, so the seniority of the two sisters is no longer relevant. The heir of line of Prince David, Earl of Strathearn, and the heir of the second marriage of King Robert II, can be found among the descendants of Lady Mary, as follows:
William Graham 7th Earl of Menteith and 1st Earl of Airth (see above, d. 1661) m. Agnes Grey John Graham, Lord Kilpont (d. 1644) m. Lady Mary Keith Lady Mary Graham m. Sir John Allardice of Allardice (d. 1676) Sir George Allardice of Allardice (d. 1709) m. Lady Anna Ogilvy James Allardice of Allardice (d. 1728) m. Mary Milne James Allardice of Allardice (d. 1765) m. Ann Barclay Sarah Ann Allardice (d. 1833)
The descendants of Sarah Ann Allardice can be found here.