Sir Gaernarfon (etholaeth)
Am yr holl gyfnod o sefydlu'r drefn o siroedd Cymru'n anfon aelod seneddol i San Steffan ym 1542, hyd 1885, Sir Gaernarfon oedd yr etholaeth a gynhwysai Uwchgwyrfai yn ei gyfanrwydd. Sir Gaernarfon oedd enw'r etholaeth eto rhwng 1918 a 1950. Rhwng 1885 a 1918, Eifion, sef hanner y sir, oedd yr etholaeth. Yn etholaeth 1929,safodd ymgeisydd seneddol cyntaf Plaid Cymru yn yr etholaeth hon, gan ennill 609 pleidlais.
Un aelod a etholwyd gan etholwyr Sir Gaernarfon, heblaw am gyfnod Cromwell yn y 1650au, pan etholwyd dau aelod dros yr etholaeth.
Aelodau seneddol 1542–1885
| Blwyddyn ethol | Aelod | Plaid | |
|---|---|---|---|
| 1542 | ?John "Wynn" ap Maredudd | ||
| 1545 | John Puleston | ||
| 1547 | John Puleston, marw 1552 ac etholwyd John Wynn ap Maredudd yn ei le | ||
| 1553 (Mawrth) | John Wynn ap Hugh | ||
| 1553 (Hydref) | Morris Wynn | ||
| 1554 (Ebrill) | Morris Wynn | ||
| 1554 (Tachwedd) | David Lloyd ap Thomas | ||
| 1555 | Sir Rhys Gruffydd | ||
| 1558 | William Wynn Williams | ||
| 1558–1559 | Robert Pugh | ||
| 1563 (Ionawr) | Morris Wynn | ||
| 1571 | John Wynn ap Hugh | ||
| 1572 (Ebrill) | John Gwynne marw 1574 ac etholwyd William Thomas yn ei le | ||
| 1584 | William Thomas marw 1586 | ||
| 1586 | Syr John Wynn | ||
| 1588 (Hydref) | Hugh Gwyn Bodvel | ||
| 1593 | William Maurice | ||
| 1597 (Hydref) | William Griffith | ||
| 1601 (Medi) | William Jones | ||
| 1604 | Syr William Maurice | ||
| 1614 | Syr Richard Wynn | ||
| 1621 | John Griffith | ||
| 1624 | Thomas Glynn | ||
| 1625 | Thomas Glynn | ||
| 1626 | John Griffith | ||
| 1628 | John Griffith | ||
| 1640 (Ebrill) | Thomas Glynn | ||
| 1640 (Tachwedd) | John Griffith (Cefnamwlch) a gafodd ei ddatgymwyso o'r Senedd, 1642 | ||
| 1647 | Syr Richard Wynn | ||
| 1653 (Senedd Barebones) | Neb wedi ei ethol | ||
| 1654 (dau aelod) | Syr John Glynn + Thomas Madryn | ||
| 1656 (dau aelod) | Sir John Glynn, wedyn Henry Lawrence (Llywydd y Cyngor); + Syr Robert Williams | ||
| 1659 | Sir William Glynne | ||
| 1660 | Syr John Glynn | ||
| 1661 | Syr Richard Wynn | ||
| 1675 | Robert Bulkeley, 2 Is-iarll Bulkeley | ||
| 1679 | style="background-color: Nodyn:/meta/color" | | Thomas Bulkeley | |
| 1689 | style="background-color: Nodyn:/meta/color" | | Sir William Williams, 6th Baronet | |
| 1697 | style="background-color: Nodyn:/meta/color" | | Thomas Bulkeley | |
| 1705 | style="background-color: Nodyn:/meta/color" | | Sir John Wynn, 5th Baronet | |
| 1713 | style="background-color: Nodyn:/meta/color" | | William Griffith | |
| 1715 | style="background-color: Nodyn:/meta/color" | | John Griffith | |
| 1740 | style="background-color: Nodyn:/meta/color" | | John Wynn | |
| 1741 | style="background-color: Nodyn:/meta/color" | | William Bodvell | |
| 1754 | style="background-color: Nodyn:/meta/color" | | Sir John Wynn, 2nd Baronet | |
| 1761 | style="background-color: Nodyn:/meta/color" | | Sir Thomas Wynn, 3rd Baronet | |
| 1774 | style="background-color: Nodyn:/meta/color" | | Thomas Assheton Smith | |
| 1780 | style="background-color: Nodyn:/meta/color" | | John Parry | |
| 1790 | style="background-color: Nodyn:Whigs (British political party)/meta/color" | | Sir Robert Williams, 9th Baronet | Whig[1] |
| 1826 | style="background-color: Nodyn:Non Partisan/meta/color" | | Sir Thomas Wynn, 3rd Baronet | Non Partisan |
| 1830 | style="background-color: Nodyn:Tories (British political party)/meta/color" | | Charles Griffith-Wynne | Tory[1] |
| 1832 | style="background-color: Nodyn:Tories (British political party)/meta/color" | | Thomas Assheton Smith | Tory[1] |
| 1834 | style="background-color: Nodyn:Conservative Party (UK)/meta/color" | | Conservative[1] | |
| 1837 | style="background-color: Nodyn:Conservative Party (UK)/meta/color" | | John Ormsby-Gore | Conservative[1] |
| 1841 | style="background-color: Nodyn:Conservative Party (UK)/meta/color" | | Edward Douglas-Pennant | Conservative[1] |
| 1866 | style="background-color: Nodyn:Conservative Party (UK)/meta/color" | | George Douglas-Pennant | Conservative |
| 1868 | style="background-color: Nodyn:Liberal Party (UK)/meta/color" | | Love Jones-Parry | Liberal |
| 1874 | style="background-color: Nodyn:Conservative Party (UK)/meta/color" | | Hon. George Douglas-Pennant | Conservative |
| April 1880 | style="background-color: Nodyn:Liberal Party (UK)/meta/color" | | Watkin Williams | Liberal |
| December 1880 | style="background-color: Nodyn:Liberal Party (UK)/meta/color" | | William Rathbone | Liberal |
| 1885 | Constituency abolished | ||
| 1918 | Constituency re-created | ||
| 1918 | style="background-color: Nodyn:Liberal Party (UK)/meta/color" | | Charles Edward Breese | Coalition Liberal |
| 1922 | style="background-color: Nodyn:Labour Party (UK)/meta/color" | | Robert Jones | Labour |
| 1923 | style="background-color: Nodyn:Liberal Party (UK)/meta/color" | | Goronwy Owen | Liberal |
| 1945 | style="background-color: Nodyn:Labour Party (UK)/meta/color" | | Goronwy Roberts | Labour |
| 1950 | Constituency abolished | ||