1820s in Wales
| 1810s | 1830s | Other years in Wales |
| Other events of the decade |
This article is about the particular significance of the decade 1820–1829 to Wales and its people.
Arts and literature
New books
- John Elias – Golygiad Ysgrythurol ar Gyfiawnhad Pechadur
- Felicia Hemans – The Forest Sanctuary
- Thomas Price (Carnhuanawc) – An Essay on the Physiognomy and Physiology of the Present Inhabitants of Britain
- David Richards (Dafydd Ionawr) – ''Cywydd y Dilyw''
Music
- John Ellis – Eliot
- Edward Jones – Hen Ganiadau Cymru
- Peroriaeth Hyfryd
- ''Seren Gomer''
Births
- 1820
- *21 May – Sir Thomas Lloyd, 1st Baronet, politician and landowner
- 1821
- *24 June – Guillermo Rawson, Argentinian politician
- *16 July – John Jones (Mathetes), preacher and writer
- 1822
- *2 March – Michael D. Jones, Patagonian settler
- 1823
- *8 January – Alfred Russel Wallace, biologist
- *March – Rowland Williams (Hwfa Môn), poet and archdruid
- *23 November – Sir John Evans, archaeologist
- 1824
- *date unknown – John Basson Humffray, political reformer in Australia
- 1825
- *7 June – R. D. Blackmore, novelist
- 1826
- *13 January – Henry Matthews, 1st Viscount Llandaff
- *1 March – John Thomas, harpist
- *8 May – George Osborne Morgan, lawyer
- *11 May – David Charles Davies, Nonconformist leader
- 1827
- *27 October – Joseph Tudor Hughes, harp prodigy
- 1828
- *30 January – John David Jenkins, philanthropist
- 1829
- *27 January – Isaac Roberts, astronomer
Deaths
- 1820
- *29 January – King George III of the United Kingdom, Prince of Wales 1751–1760
- *16 June – Thomas Jones of Denbigh, Methodist preacher and writer
- *27 June – William Lort Mansel, bishop and academic
- *23 August – John Randles, harpist
- *28 August – Henry Mills, musician
- 1821
- *2 May – Hester Thrale, diarist
- *7 August – Caroline of Brunswick, former Princess of Wales, 53
- 1822
- *30 March – David Thomas (Dafydd Ddu Eryri), poet
- *date unknown – Stephen Kemble, actor, brother of Sarah Siddons
- 1823
- *26 February – John Philip Kemble, actor, brother of Sarah Siddons
- 1825
- *24 February – Thomas Bowdler, editor
- *9 June – Abraham Rees, encyclopaedist
- *10 August – Joseph Harris (Gomer), Baptist minister, poet and editor
- 1827
- *date unknown – Helen Maria Williams, novelist and poet
- 1828
- *September – William Madocks, landowner
- 1829
- *26 January – Benjamin Millingchamp, collector of manuscripts
- *June – Elizabeth Randles, harpist