21st (Prince Albert Victor's Own) Cavalry (Frontier Force)

Known as 21st Cavalry and Daly's Horse

Chronology

1849 raised as 1st Regiment of Punjab Cavalry by Henry Daly
1851 retitled as the 1st Regiment of Cavalry, Punjab Irregular Force
1865 became the 1st Regiment of Cavalry, Punjab Frontier Force
1903 became 21st (Prince Albert Victor's Own) Cavalry (Frontier Force), Daly's Horse
1922 merged with the 23rd Regiment of Cavalry, Punjab Frontier Force to become 11th Prince Albert Victor's Own Cavalry (Frontier Force)

11th Prince Albert Victor's Own Cavalry (Frontier Force) Wikipedia
Sir Henry Dermot Daly 1821-95 Oxford Dictionary of National Biography
Pavo Cavalry by Major Agha H Amin (Retired) pavocavalry.blogspot.com
Watercolour by Charles James Lyall: 1896. 1st Regt. of Punjab Cavalry Brown Digital Repository, Brown University Library.
Headstone carving for 21st Cavalry used by the Commonwealth War Graves Commission for First World War deaths. Appears to be based on the regimental badge of that time. From a CWGC webpage "International differences" shapingoursorrow.cwgc.org

History Of 1st Punjab Cavalry 1887. Archive.org, mirror from the Digital Library of India.