United Kingdom National Football Team

I asked in post-1900 but nobody could come up with a good scenario, so with a POD in the 19th century, when and how would the UK get one national football team, preferably accompanied by a unified FA and top league(s)?
 
I'm not so sure you would. Given that Rugby Union still has the individual home nations and they started about the same time. And before any body says Lions they only come out to play every 4 years. Actually it could work like that the UK team has historically only played every 4 years first against France and then the rest of the world.
Or football is like cricket and although there are Scottish, Welsh and Irish teams the England team can pick anyone born or naturalised in the UK. This would have had to have a POD around 1863.
 
Have football develop outside Britain, or at least modern football. Then when teams start playing it the UK sets up a school/association to join in. It then fields a team to an international tournament and presto there is tradition of a UK team.
 
If you look at the first internationals it was England vs Scotland for both rugby (1871) and football (1872).

Have a POD were the first sporting international was between France and England it is far more likely that Scots / Welsh and Irish players would be picked for a "national side".

Alternatively have some non-English men on the organising committee.
 
If the Scottish clubs didn't form their own football association, as it did in 1873, the game might have developed differently.
 
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