Wasn't it the Conservatives who used to oppose Britain joining the EU?

[muriel_volestrangler]

4. They still do oppose it, mostly

See page 6 of this: https://www.icmunlimited.com/wp-content/uploads/2016/06/13-Jun.pdf

proportion voting 'leave' by party they voted for in 2015:
UKIP 95%
Con 51%
Lab 37%
Lib Dem 25%
Green 18%
Other 46%

In general, it's the centre that is pro-EU, the right and far left that is anti. Over the years, the size of the anti-EU Tory faction has grown (and spawned UKIP), and the size of the Labour anti-EU faction has decreased. The main reason Leave voters give is immigration - they want to stop the free movement of EU citizens into the UK for work.

Page 36 of this: https://www.ipsos-mori.com/Assets/Docs/Polls/pm-16-june-2016-tables.pdf

52% of 'leave' say "The number of immigrants coming into Britain" is a very important reason for their vote, compared with just 22% saying "Britain's ability to make its own laws". Another 14% say "Impact on public services/housing", and 10% "The cost of EU immigration on Britain's welfare system".