John Howard Parnell was an older brother of Charles Stewart Parnell. Both brothers represented Meath in the House of Parliament.

Born in 1843, John Howard Parnell was the fifth child of John Henry and Delia Parnell. Educated in France and England, he was awarded a Certificate in Geology. Due to terms in a bequest to the family it was his younger brother, Charles, who inherited the family estates at Avondale while John inherited lands in Armagh. 

In his twenties John Howard Parnell went to Valley, Alabama in 1867 to purchase a plantation. Fortunes were to be made in the aftermath of the American Civil War, advised his American uncle, Charles Stewart. He purchased the 1,482 acre estate of Colonel Hugeley, just to the south of West Point, Alabama. Intending to grow cotton, he later became involved in peach growing. John is said to have planted up to 700 acres of peach trees, one of the biggest orchards in America at the time. He invented a method for transporting frozen fruits. In 1872 his brother, Charles Stewart Parnell, visited the Alabama estate prior to his entry into politics. John regularly visited Atlanta, New York and made regular visits back to Ireland. After a crop failure in 1883 John sold his lands but maintained an interest in a fruit industry and invested in other American fruit farms. In recent years the Parnell Society of Ireland established the John Howard Parnell Memorial Garden Park in Valley, Alabama, U.S.A.

In 1874 Charles persuaded John to stand for election in Wicklow in his place but he was unsuccessful, finishing at the bottom of the poll.

Following the death of Charles in 1891 John returned to Ireland and took over the family property at Avondale ignoring his brother’s wishes that his estates go to his wife Katherine. John stood as a Parnellite candidate for West Wicklow in 1892 but was not successful. In the 1895 election he took the South Meath seat winning narrowly over the sitting anti-Parnellite, Jeremiah Jordan, by 43 votes. As an M.P. John rarely spoke and was noted for his chess playing, even taking part in a match against members of the American House of Representatives. He is recorded as speaking in the House of Commons eleven times in 1896 and twice in 1897. 

In March 1898 John was elected City Marshal of Dublin. The post was worth £1000 a year. John had received the post as he said without additional remuneration he would lose Avondale, the family home.  The estate was heavily mortgaged and John sold it the following year. Five years later in 1904 it was purchased by the state at the instigation of Horace Plunkett and Avondale was developed with the first silvicultural experimental plots being laid out along the lines of a continental forest garden. John was also Registrar for Pawnbrokers for Ireland so he was master of pawns and pawnbroking.

John intended to stand again for South Meath in 1900 and attended the nomination venue, expecting to be the only candidate. However J.L. Carew who was under pressure in his College Green constituency for having attended a royal event was nominated. John did not have the required fee to pay for his nomination in a contested election and so Carew was elected uncontested. Carew later said he had been nominated without his knowledge or consent and offered to withdraw but never actually did.

When Carew died in 1903 John did not receive the nomination from the Irish Party for South Meath so he contested the seat as an independent nationalist but he lost to the official candidate, David Sheehy. In 1907 at the age of 63 he married Olivia Isabella Smythe, daughter of Colonel James Smythe and widow of Archibald Matier of Carlingford.

In Ulysses Bloom sees John Parnell wandering the streets. Later Boylan and Haines see Parnell playing chess against himself. John Parnell tells Bloom that he is the greatest Irishman since Charles Stewart Parnell.

In 1916 John wrote a memoir of this brother, Charley. It is an affectionate account. He devoted a section to the superstitions of his brother – his fear of the colour green, the number thirteen and the month of October. John Howard Parnell died on 3 May 1923.