List of Battles and Secondary Actions comes from British Nomenclature for the Battle of the Somme: Refer Battle of the Somme for transcribed list
Where pages already exist and are called "Battles" rather than engagements, actions or "capture of", the original page name was moved when the article was completed
Full Secondary Action list added as red-links, most written by 1 November 2014
Revised headings according to Record of Battles and Engagements, James 1924; two red links to go