Population model of some major ethnicities of europe if European migration to Americas and Australasia had not happened.
Expected population 2021.
UK- 25.87 crore
Italy- 13.71 crore
Germany- 13.27 crore
France- 9.21 crore

Clarly there r more Brits, irish, italians and french outside europe.
Also Britain and Ireland were th Java of 17th century with extreme high population density and growth due to industrial revolution. This extreme population,resource requirements was prime factor of colonialism.

Germans, French and Brits settled mostly in Usa, Canada and Australasia.
Italians mass migrated to Argentina and venezuela.
This thread excludes native americans who adopted spanish or portugeuse identity as sapniard or portugeuse migration to new world was not that huge.