It's not just for WW1. It's for all conflicts.

This version was the tune only, It’s well worth listening to a version of this with the words being sung

This event is the annual Service of Remembrance held at the Royal Albert Hall to honour all the  British and Commonwealth service men and women who have given their lives for their country during WW1, WW2 & all conflicts since.
Please understand that this is an extremely poignant, serious and important event and should be approached with total and complete respect.
This service allows the whole country and Commonwealth to mourn those that made the ultimate sacrifice. Please remember the purpose during your commentary.

The musicians in the blue uniforms are members of the Royal Marines Band Service.  When on active service they are medics, stretcher bearers, ambulance drivers etc.

From Scotland, and I know you do not know but all of this watched in silence

Remembrance Day is like Veteran's Day in the US - both observed on 11th November - the data in 1918 when hostilities ended during WW1. You are watching a festival held in London to mark that event.  Its now a day that refers to all armed conflicts.

Please show respect and give comment after.....this sound is deeply loved emotionally by many thank you for future

I have lived 83 years  in the United Kingdom, and am amazed to learn that the USA doesn’t have a Festival of Remembrance like we do.  Every year the Sunday closest to the 11th November is Armistice Sunday, originally to celebrant the sacrifice of those who didn’t return after the end of the first World War.  This festival has since become the day when we remember the fallen of two World Wars and the many conflicts since.  The Festival of Remembrance that you were watching takes place at the Royal Albert Hall in London every year, on the Saturday before Armistice Sunday, in the presence of the Monarch.  It comprises serving members of the three branches of military services, Navy, Army and Airforce.  Also present are representatives of retired service personnel, representatives of families who have lost members whilst serving abroad.  So I guess you could say that it is an important occasion every year, for a few weeks before Armistice Sunday volunteers are out on the streets selling those Poppies, which were symbolic of the poppies that grew on Flanders Field once the guns fell silent at the end of the War that was supposed to end all wars 11th November 1918.  The song - I vow to thee my Country, all earthly things above, entire and whole and perfect, the Service of my love. Carry great symbolism for us in the UK. ❤

No one does pomp and ceremony like the British. Every regiment of the British army has it's own band it dates back to the days where orders were relayed by drum and bugle

The music is the middle section of Jupiter, the Bringer of Jollity from The Planets, by Gustav Holst. Words were added about 1920-ish. The musicians belong to various branches of the military, and they are full-time musicians. In combat they are usually stretcher-bearers, medical orderlies and other similar roles.

For the fallen in all wars it's inside the royal Albert Hall in london

Remembrance was the clue .To talk through the entire length was not a good thing.Remembrance - a time of quiet reflection.

London Calling: As per previous comment this is from Planets composed by Gustav Holst and is usually titled ‘Jupiter bringer of jollity’ and is also usually performed in happy upbeat way. Well worth a listen.

One of my favourite versions of this song is on YouTube by The Bands of HM Royal Marines - entitled "I Vow To Thee My Country | The Bands of HM Royal Marines" - I would LOVE you to react to this, and YES it has drums! It's also amazing that it's performed by active personnel. For anyone else reading this comment, check it out too, it's amazing, and thumbs up if you like it so Franchesca sees it!

He saluted at the end to the Queen, as the Royal Family attend

This is the Royal British Legions Festival of Remembrance its a yearly even to remember those who died in WW1, WW2 and all conflicts after and those wound in the line of duty and retired all the music is carried out by British military bands it honestly a beautiful and emotional watch its the one time of year were we have our patriotism is on full display.

The music is from Gustav Holst's "The Planets" suite, specifially the "Jupiter" movement.  The words "I vow to thee my country" were set to the music to form a hymn.

You ought to watch the Festival of Remembrance 2022 (held every year). Luke Evans (the actor) sings this song.
The Festival is held at the Royal Albert Hall in remembrance of all the servicemen and women (UK and the Commonwealth) who lost their lives in the WW1, WW2 and subsequent conflicts.
We have just had the Festival for this year the Saturday nearest to 11th November, and then the next day we have the monarch and Royal Family, politicians, clergy and represetatives of the Commonwealth lay wreaths at the Cenotaph in London. Followed by, this year 10,000, servicemen and women walking past laying their wreaths. Very few men left from WW2.

You simply must see a version with the words, it would give you a much clearer idea what this is actually about.

Listen to I vow to thee my country, sung by Ramin Karimloo. You will be in tears.