Mac Diarmada (anglicised as McDermott or MacDermot), also spelled Mac Diarmata, is an Irish surname, and the surname of the ruling dynasty of Moylurg, a kingdom that existed in Connacht from the 10th to 16th centuries. The last ruling king was Tadhg mac Diarmata, who ruled until 1585.

The progenitor of the family was Dermot mac Tadhg Mor, 7th King of Moylurg, who reigned from 1124 to 1159. He was a vassal and kinsman of the Ó Conchubhair, Kings of Connacht; their common ancestor was Tadg mac Cathal, King of Connacht from 925 to 956. They were based at McDermott's Castle, Lough Key.

Later offshoot septs of the dynasty included the families of MacDermot Roe.

Moylurg ceased to exist as a kingdom in the late 16th century, though the senior line of the MacDermot's continued to live a sometime poverty-stricken and precarious existence despite land confiscations and the oppression of the Penal Laws. During this era they were popularly accorded the title Prince of Coolavin;^{[citation needed]} the current incumbent is Francis MacDermot,^{[citation needed]} who succeeded by birthright to his father Rory MacDermot who died on 6 May 2021.^{[1][citation needed]}

Variations of the name include :

• McDermott, MacDermott
• MacDiarmada, MacDiarmata
• MacDermot Roe, MacDermott Roe
• McDermitt
• McDermett
• McDiarmid, MacDiarmid, Irish and Scottish language variants ultimately from Irish
• McDormand, MacDormand
• Kermode, Manx language variant^[2]
  • Kermit, variant of Kermode

and others.

• Conchobair MacDermot
• Dermot MacDermot
• Frank MacDermot
• Galt MacDermot (1928–2018), Canadian-American composer, pianist
• Hugh Hyacinth O'Rorke MacDermot
• Niall MacDermot
• Niall Anthony MacDermot
• Rory MacDermot
• Tomaltach na Cairge MacDermot

• Alice McDermott, writer
• Alister McDermott, cricketer
• Andrew McDermott (singer) (born 1966), English singer
• Andrew McDermott (footballer) (1889–1915), Scottish footballer
• Andy McDermott, author
• Bill McDermott, executive
• Brian McDermott (disambiguation), several people
  • Brian McDermott (rugby league), rugby coach
  • Brian McDermott (footballer), football manager of Reading F.C.
  • Brian McDermott (murder victim), child who was murdered in Belfast in 1973
• Bobby McDermott, basketball player
• Charles McDermott (disambiguation), several people
• Charlie McDermott, American actor
• Chris McDermott (born 1963), Australian rule player from South Australia
• Christopher McDermott (born 1989), British handball player and coach, Olympian London 2012
• Craig McDermott, cricketer
• Dan McDermott, expert dispatcher of flights at Stansted Airport
• David McDermott, English footballer
• Dean McDermott (born 1966), Canadian-American actor
• Doug McDermott (born 1992), American basketball player; son of Greg McDermott (see below)
• Drew McDermott, computer scientist
• Dylan McDermott (born 1961), American actor
• Eoghan McDermott (born 1983), Irish radio and television presenter
• Eugene McDermott, geophysicist, philanthropist; co-founder, Chairman, Director of Texas Instruments
• Gerald McDermott, American author, illustrator, graphic designer, and film maker
• Greg McDermott (born 1964), American basketball coach
• Helen McDermott, British radio and television presenter, best known for her work at Anglia Television
• James McDermott (disambiguation), several people
  • James J. McDermott, Jr., former CEO and chairman of Keefe, Bruyette & Woods
• Jim McDermott (born 1936), American politician
• John McDermott (disambiguation), several people
  • John McDermott (golfer), American golfer
• Joseph McDermott (disambiguation), several people
• Kathleen McDermott (born 1977), Scottish actress, singer, model, and make-up artist
• Kevin McDermott (disambiguation), several people
  • Kevin McDermott (singer–songwriter), Scottish singer-songwriter
  • Kevin McDermott (American football), American football player
• Lloyd McDermott, Australia's first indigenous barrister and rugby union player
• Melissa McDermott, CBS news anchor and reporter
• Michael McDermott (disambiguation), several people
  • Michael McDermott, software engineer who carried out the 2000 Wakefield massacre
• Michael McDermott (musician), Chicago singer-songwriter
• Mickey McDermott, baseball pitcher
• Mike McDermott (disambiguation), several people
• Neale McDermott, football player
• Neil McDermott (born 1980), British actor
• Nicola McDermott (born 1996), Australian olympic highjumper
• Nora McDermott (1927–2013), Canadian basketball and volleyball player, coach and physical education teacher
• Patrick McDermott (disambiguation)
• Paul McDermott, Australian comedian
• Paul Francis McDermott (born 1965), Australian electro-pop musician, performs as Paul Mac
• Phelim McDermott (born 1963), English actor and stage director
• Robert McDermott (disambiguation), several people
• Roe McDermott, Irish film critic, younger brother of Eoghan
• Ted McDermott (Thomas McDermott) nicknamed Songaminute Man, Vocalist and Entertainer, "The Songaminute Man"
• Terry McDermott (disambiguation), several people
  • Terry McDermott, football player
• Thomas McDermott (disambiguation), several people
• Tracey McDermott, acting chief executive of Britain's Financial Conduct Authority (FCA)
• William Dermott Molloy McDermott, Roman Catholic bishop

• Ambrose MacDermott, Bishop of Elphin from 1707 to 1717
• Cormac MacDermott
• G. H. MacDermott
• John MacDermott, Baron MacDermott
• Marshall MacDermott, (c.1791 – 1877) British Army officer and Australian politician
• Mercia MacDermott (born 1927), English writer and historian
• Seán Mac Diarmada, a.k.a. Seán MacDermott

• Frances McDormand, actress

• McDermott Field, a baseball stadium in Idaho that was replaced by Melaleuca Field
• McDermott, Ohio, a census-designated place in western Rush Township, Scioto County, Ohio, United States.^[3]

• Kings of Uí Díarmata
• Dermott (disambiguation)
• Irish nobility
• Irish royal families

• MacDermot Clan Association website^[usurped]
• MacDermot (No.1) family pedigree by John O'Hart
• McDermott DNA Project

Surname list

This page lists people with the surname Mac Diarmada.
If an internal link intending to refer to a specific person led you to this page, you may wish to change that link by adding the person's given name(s) to the link.