Question: What 1st Earl of Avon also signed the Anglo-Soviet Treaty of 1942?
Context: Earl of Berkshire is a title that has been created twice in the Peerage of England.  It was created for the first time in 1621 for Francis Norris, 1st Earl of Berkshire.  For more information on this creation (which became extinct on his death in 1622), see the Earl of Abingdon and also the Earl of Lindsey.  The second creation came in 1626 in favour of Thomas Howard, 1st Viscount Andover.  He was the second son of Thomas Howard, 1st Earl of Suffolk, second son of the second marriage of Thomas Howard, 4th Duke of Norfolk.  His mother was Katherine, daughter of Sir Henry Knyvett of Charlton in Wiltshire.  Howard had already been created Baron Howard of Charlton, in the County of Wiltshire, and Viscount Andover, in the County of Southampton, in 1622.  These titles are also in the Peerage of England.  Lord Berkshire succeeded to the Charlton estate through his mother in 1638.  He was succeeded by his eldest son, the second Earl.  He had already in 1640 been summoned to the House of Lords through a writ of acceleration in his father's junior title of Baron Howard of Charlton.  He had no sons and on his death in 1679 the titles passed to his younger brother, the third Earl.  He represented Wallingford in the House of Commons.  He also died without male issue and was succeeded by his great-nephew, the fourth Earl.  He was the grandson of the Hon. William Howard, fourth son of the first Earl.  In 1745 he succeeded his third cousin as eleventh Earl of Suffolk.  For further history of the titles, see the Earl of Suffolk. Lieut.-Gen.  Sir James FitzThomas Butler, 1st Duke of Ormond, 1st Marquess of Ormond, 12th Earl of Ormond, 5th Earl of Ossory, 4th Viscount Thurles, 1st Baron Butler of Llanthony, 1st Earl of Brecknock KG, PC (19 October 1610 – 21 July 1688) was an Anglo-Irish statesman and soldier, known as Earl of Ormond from 1634 to 1642 and Marquess of Ormond from 1642 to 1661.  Following the failure of the senior line of the Butler family, he was the second of the Kilcash branch to inherit the earldom.  His friend, the 1st Earl of Strafford, caused him to be appointed the commander of the Cavalier forces in Ireland.  From 1641 to 1647, he led the fighting against the Irish Catholic Confederation.  From 1649 to 1650 he was the leading commander of the Royalist forces in the fight against the Cromwellian conquest of Ireland.  In the 1650s he lived in exile in Europe with King Charles II of England.  Upon the restoration of Charles to the throne in 1660, Ormonde became a major figure in English and Irish politics, holding many high government offices. The Twenty-Year Mutual Assistance Agreement Between the United Kingdom and the Union of Soviet Socialist Republics or Anglo-Soviet Treaty established a military and political alliance between the USSR and the British Empire during World War II, and for 20 years after it.  The treaty was signed in London on 26 May 1942 by British Foreign Secretary Anthony Eden and by Soviet foreign minister Vyacheslav Molotov. Henry Howard, 10th Earl of Suffolk (1 January 1706 – 22 April 1745) was the only child of Henrietta Howard, Countess of Suffolk and Charles Howard, 9th Earl of Suffolk.  He was styled Lord Walden from 1731 to 1733.  He married Sarah Inwen, daughter of Thomas Inwen and Sarah Hucks, on 13 May 1735, but died on 22 April 1745 at age 39 with no surviving issue and no brothers to whom the title could be passed.  The line of Earls of Suffolk back to Henry's great-great grandfather Thomas Howard, 1st Earl of Suffolk thus died out, and the title passed to a great grandson of the 1st Earl (via the 1st Earl's second son Thomas), Henry Howard, 4th Earl of Berkshire. Robert Anthony Eden, 1st Earl of Avon, (12 June 1897 – 14 January 1977) was a British Conservative politician who served three periods as Foreign Secretary and then a relatively brief term as Prime Minister of the United Kingdom from 1955 to 1957. James Hay, 2nd Earl of Carlisle (1612 – 30 October 1660) was the Earl of Carlisle (2nd Creation), succeeding James Hay, 1st Earl of Carlisle.  Hay was the second son of the 1st Earl, a Scottish nobleman, and his wife Honoria, heir to Edward Denny, 1st Earl of Norwich. Marquess of Ely, of the County of Wexford, is a title in the Peerage of Ireland.  It was created in 1800 for Charles Loftus, 1st Earl of Ely.  He was born Charles Tottenham, the son of Sir John Tottenham, 1st Baronet, who had been created a baronet, of Tottenham Green in the County of Wexford, in the Baronetage of Ireland in 1780, by Elizabeth, daughter of Nicholas Loftus, 1st Viscount Loftus, sister and heiress of Henry Loftus, 1st Earl of Ely (see Viscount Loftus and Earl of Ely for earlier history of the Loftus family).  In 1783 he succeeded to the Loftus estates on the death of his maternal uncle the Earl of Ely and assumed the same year by Royal licence the surname of Loftus in lieu of his patronymic.  In 1785 he was raised to the Peerage of Ireland as Baron Loftus, of Loftus Hall in the County of Wexford.  It was sold by the family in 1917 and is today owned by the Quigley family. The Ailesbury Mausoleum situated in the churchyard of St Mary's Church, Maulden, in Bedfordshire, is a Grade II listed structure built in 1656 by Thomas Bruce, 1st Earl of Elgin (1599–1663) (father by his 1st wife of Robert Bruce, 2nd Earl of Elgin, 1st Earl of Ailesbury (1626-1685)), of nearby Houghton House in the parish of Maulden, for the purpose of housing the coffin and "splendid monument" of his second wife, Lady Diana Cecil (d.1654), a daughter of William Cecil, 2nd Earl of Exeter and widow of Henry de Vere, 18th Earl of Oxford.  In the opinion of the architectural historian Sir Howard Colvin (1991) it is one of the first two free-standing mausoleums ever built in England, together with the Cabell Mausoleum at Buckfastleigh in Devon. Anne Clarissa Eden, Dowager Countess of Avon ("née" Spencer-Churchill; born 28 June 1920) is the widow of Anthony Eden, 1st Earl of Avon (1897–1977), who was British Prime Minister from 1955 to 1957.  She married Eden in 1952, becoming Lady Eden in 1954 when he was made a Knight of the Garter, and then becoming Countess of Avon in 1961 on her husband's elevation to the peerage.  She is also the niece of the prime minister Winston Churchill.  Her memoir, sub-titled "From Churchill to Eden", was published in 2007 under the name of Clarissa Eden. Hugh de Courtenay, 1st/9th Earl of Devon (14 September 1276 – 23 December 1340) was the son of Sir Hugh de Courtenay (died 1292), feudal baron of Okehampton in Devon, by his wife Eleanor le Despenser (died 1328), sister of Hugh le Despenser, 1st Earl of Winchester.  Forty-one years after the death of his cousin, Isabel de Forz, "suo jure" 8th Countess of Devon (1237–1293) (née de Redvers, eldest daughter of Baldwin de Redvers, 6th Earl of Devon (1217-1245)), letters patent were granted by King Edward III, dated 22 February 1335, declaring him Earl of Devon, and stating that he 'should assume such title and style as his ancestors, Earls of Devon, had wont to do'.  This thus made him 1st Earl of Devon, if the letters patent are deemed to have created a new peerage, otherwise 9th Earl of Devon if it is deemed a restitution of the old dignity of the de Redvers family and he is deemed to have succeeded the "suo jure" 8th Countess.  Authorities differ in their opinions and thus alternative ordinal numbers exist for this Courtenay earldom.
Answer: Anthony Eden