If memory serves, the last time there was a European Army worthy of the name was in 1900, during the Chinese upheaval now called the 'Boxer Rebellion'.
Admittedly, most of the force was made up by large contingents from Japan and Russia, plus the US, but the rest of the troops were from the UK, France, Italy, Germany and Austria-Hungary, so a true European army.
By all accounts, this assemblage performed well militarily, disregarding the various atrocities and pillaging that took place.