North West Europe
Has been fought in and over from Ancient times, from when Julius Caesar gave the Gauls a slapping (58bc-ish) through to WW2 (1940) when Jerry gave the Gauls another slapping and we had to go and boot them back to Berlin (1944-45), having already had to do the same in WW1. To be honest it would save everyone a lot of trouble if EVERYONE gave the frogs a slapping every 50 years or so.
Too many battles in the area to list them all, which is why alot of regiments just have North-West Europe 1944-45 as a battle honour. Look through the pages for WW1 and WW2 for an idea of the bigger ones in the 20th century.