How can I find out what weekday a certain date fell on?

 There are three main options: calendars on software packages, newspapers and directories or the Handbook of Dates.

Calendars on software packages

Some personal organiser packages for computers include calendar or diary functions which are back-dated by several centuries. However, these simply extend the current (Gregorian) calendar back to the earliest date in the package. This means that the calendar on your computer diverges from the calendar which operated in Scotland prior to 14 September 1752. For dates prior to 14 September 1752, you will need to consult Handbook of Dates for Students of English History ed. by C. R. Cheney (Cambridge University Press, 1995).

Newspapers and directories

If it is a date in the 19th or 20th centuries you should look at the back copy of a newspaper for that date. Many newspapers are now available through the British Newspaper Archive website (available free of charge in the National Library of Scotland or with a subscription elsewhere) https://www.britishnewspaperarchive.co.uk/

Alternatively, you could consult a Post Office Directory for the year in question. Post Office Directories include calendars for the year of publication, and these also include the dates of local holidays. Runs of Post Office Directories from the late 18th century to the 1970s are held by large reference libraries, such as Edinburgh City Libraries and the Mitchell Library, Glasgow.

Handbook of Dates

1. Handbook of Dates for Students of English History ed. by C.R. Cheney (Cambridge University Press, 1995) is one of the most useful books for historians in Britain. Pages 83-160 allow you to work out a calendar for any year using fixed tables for all possible dates for Easter. Cheney’s tables will also allow the calculation of any date from 500AD onwards, but pay attention to discrepancies in the calendars of different parts of Europe between the 16th and 20th centuries.