The Execution of Lady Jane Grey: 12 February 1554.

The painting shows the last moments of seventeen-year old Jane Grey proclaimed Queen of England after the death of young King Edward VI a Protestant like her. 

She reigned for just nine days in 1553;  Mary Tudor the Catholic daughter of Henry VIII and Catherine of Aragon, had her convicted of high treason and sentenced to death in the Tower of London.
Henry VIII of England on Horseback 

Henry VIII, second Tudor dynasty king of England and Ireland  (28 June 1491 – 28 January 1547) is known for his 6 marriages: Catherine of Aragon. Anne Boleyn, Jane Seymour, Anne of Cleves, Catherine Howard and Catherine Parr.
He is also responsible for the separation of England from the Roman Catholic papal authority, but also for the union of England and Wales.

The Queen´s Foot Guards

Traditionally, there are 4  guards in front of Buckingham Palace and St. James Palace when the Queen is in residence and 2 when she´s away.  
There are 5 regiments of Foot Guards: Grenadier, Coldstream, Scots, Irish and Welsh. 
They stand still for no more than 10 minutes at a time, are on duty for 2 hours and then rest for 4. 
All Summer, the Queen´s Foot Guards in London, England wear their red tunics. 
The grey coats are used in the Winter because of their larger length and thickness.
The 1.5 lb/45.7 cm bearskin hat used by the guards is intended to make them appear taller and scary; they are made from real "culled" Canadian brown bears. 
The bearskin hats were first used in 1815, after Napoleon´s defeat in the battle of Waterloo.