The War Office was formerly called the Milton Vaults and was first opened by my Great Great Grandfather at the start of the 20th Century. His name was Charles Thour and he was originally from London but moved to Glasgow in his late teens with his father and siblings. The pub was indeed one of a few venues in Motherwell where local could enlist to fight in the First World War, hence the unofficial name change (until relatively recently). What makes the story more interesting is that Charles' father (also Charles) was a German national living in Motherwell at this time. Germans were being deported from the UK during the war, so he lied about his nationality to the locals in his son's pub and declared himself to be Dutch and became known as the 'Dutchman'.
After Chalres jnr died, his sons (Charles and Stephen) opted not to take over the running of Tehran vaults and instead it was passed over to his son-in-law Walter
Hope this helps
I have photographs of the original building when it opened which are fascinating.
