It depends on the year. For example, in 1594, the Lord Mayor of London was John Spencer.
The lord mayor of London, Sir William Walworth (at that time) is reported to be the killer.
Lord Mayor is the title of the Mayor of a major city. Great Britain is a country and as such doesn't have a Lord Mayor.
Ken Livingstone was Mayor of London in 2007. The present Mayor is Boris Johnson.
The Mayor changes every year.
On 3rd May 2008 Boris Johnson became the newly elected Mayor of London
Thomas Lodge - Lord Mayor of London - died in 1584.
Richard Martin - Lord Mayor of London - died in 1617.
William Rowe - Lord Mayor of London - died in 1593.
In the case of London - "The Rt Hon The Lord Mayor of the City of London"
If it is the first word in a sentence, or if you are talking about the Lord Mayor (London's).
Dick Whittington, who did have a cat but didn't become Lord Mayor because of it. Incidentally, there really was a Lord Mayor of London called Richard Whittington, so its not a fairy tale, it's fact.
Mansion House
Sir William Staines
The cast of The Lord Mayor of London - 1914 includes: David Lloyd George as himself Thomas Vensittart Bowater as himself
Mayor Boris Johnson of the conservative party
Dame Mary Donaldson - 1983
The City of London and the city called London are two distinct places. The head of the City of London is the 'Lord Mayor of the City of London'. This should not be confused with the 'Mayor of London', who is in charge of the whole of Greater London.