Question: Which writer was born earliest, Mary Gordon or H. L. Mencken? 

Context paragraphs:
August Mencken Sr.: August Mencken Sr. (1854–1899) was the father of writer H. L. Mencken.  August Mencken founded the "Aug.  Mencken & Bro."  cigar factory in 1873 with a starting capital of $44 ($23 of his own money, $21 of his brother's).  A member of Baltimore's German American community, August was recalled by his son as a high-tariff Republican who ran a nonunion factory and viewed the eight-hour day as ""a project of foreign nihilists to undermine and wreck the American Republic"".  H. L. also recalled that his father downed a generous tumbler of rye whiskey before every meal, including breakfast.

William Hamilton, Duke of Hamilton: William Douglas-Hamilton, Duke of Hamilton, KG, PC (24 December 1634 – 18 April 1694), was a Scottish nobleman and politician.  Born Lord William Douglas.  He was the eldest son of William Douglas, 1st Marquess of Douglas by his second wife Lady Mary Gordon, a daughter of George Gordon, 1st Marquess of Huntly.

Mary Gordon (writer): Mary Catherine Gordon (born December 8, 1949) is an American writer and the McIntosh Professor of English at Barnard College.  She is best known for her novels, memoirs and literary criticism.

Marion Bloom: Marion Bloom (1891–1975) was H. L. Mencken's lover for much of the early twentieth century - eventually becoming close enough that they seriously considered marriage.  They first met February 1914 when Bloom visited the office of "Baltimore Sun".  Mencken and Bloom ended their relationship in the early 1920s, though Bloom continued to admire Mencken.  Their love letters were published in "In Defense of Marion: The Love of Marion Bloom & H.L. Mencken" in 1996 (ISBN  ).

Robert Balfour, 6th of Balbirnie: Lieutenant-General Robert Balfour of Balbirnie (3 May 1772 – 31 October 1837) was a son of John Balfour of Balbirnie and Mary Gordon, daughter of James Gordon of Ellon.

H. L. Mencken: Henry Louis Mencken (September 12, 1880 – January 29, 1956) was an American journalist, satirist, cultural critic and scholar of American English.  Known as the "Sage of Baltimore", he is regarded as one of the most influential American writers and prose stylists of the first half of the twentieth century.  He commented widely on the social scene, literature, music, prominent politicians and contemporary movements.  His satirical reporting on the Scopes trial, which he dubbed the "Monkey Trial", also gained him attention.

Treatise on the Gods: Treatise on the Gods (1930) is H. L. Mencken's survey of the history and philosophy of religion, and was intended as an unofficial companion volume to his Treatise on Right and Wrong (1934).  The first and second printings were sold out before publication, and eight more printings followed.  Its first edition received a major 5-column review in the "New York Times", written by one P.W. Wilson; and the Marxist literary critic Granville Hicks called it "the best popular account we have of the origin and nature of religion."  However, the Protestant theologian Reinhold Niebuhr, writing in the "Atlantic Monthly", claimed that "It is only in dealing with moral and social issues that [Mencken] achieves the heights of complete detachment, and in this case the detachment is that of a cynic rather than that of a scientist."  By the end of its first year "Treatise" had sold thirteen thousand copies.  By 1940 its popularity had waned, and although it went temporarily out of print in 1945, Mencken considered it "my best book, and by far."  At the request of its original publisher Alfred A Knopf, Mencken wrote a revised edition (1946), eliminating (among other changes) a controversial quote about Jews:

The Philosophy of Friedrich Nietzsche: The Philosophy of Friedrich Nietzsche is a book by H. L. Mencken, the first edition in 1907.  The book covers both better and lesser known areas of Friedrich Nietzsche's life and philosophy.  It is notable both for its suggestion of Mencken's still-developing literary talents at the age of 27 and for its impressive detail as the first book on Nietzsche written in English (only seven years after Nietzsche's death) considering the lack of reliable interpretations of Nietzsche in the Western sphere of letters at the time; Mencken prepared for writing this book by reading all of Nietzsche's published philosophy, including several works in the original German.

H. L. Mencken House: The H. L. Mencken House was the home of "Baltimore Sun" journalist and author Henry Louis Mencken, who lived here from 1883 until his death in 1956.  The Italianate brick row house at 1524 Hollins Street in Baltimore was designated a National Historic Landmark in 1985.  Mencken wrote of his home: "“I have lived in one house in Baltimore for nearly 45 years.  It has changed in that time, as I have—but somehow it still remains the same... It is as much a part of me as my two hands.  If I had to leave it I’d be as certainly crippled as if I lost a leg.”"

A Book of Prefaces: A Book of Prefaces is H. L. Mencken's 1917 collection of essays criticizing American culture, authors, and movements.  Mencken described the work as "[My] most important book in its effects upon my professional career."  In fact, the book was considered vitriolic enough that Mencken's close friend Alfred Knopf was concerned about publishing it because of the massive increase in patriotism during World War I in America.

Supporting paragraphs: Mary Gordon (writer) H. L. Mencken
Answer: Mencken