The football championship was followed by the game Pokemon Go, the late singer David Bowie and US President-elect Donald Trump in its rankings.
Google's list is based on words and phrases that stand out from the norm to get round the fact that an unfiltered version would be little changed from one year to the next.
The top global term was Pokemon Go.
Perhaps surprisingly, the death of Prince ensured the singer was more "googled" by UK users than either Brexit or EU referendum - the two phrases are grouped together in the firm's rankings.
The US firm has also analysed how its search tools are used to rank UK queries by topic, giving further insight into users' fads and preoccupations over the past 12 months.
Pikachu and his fellow monsters were obviously on a lot of minds because "How to play Pokemon Go?" was not only the most popular "How to...?" question, but "What is Pokemon Go?" was also the most popular "What is...?" entry too.
Prince Harry's girlfriend Meghan Markle may have only hit the headlines in late October - when their relationship was still a rumour - but she managed to become the UK's most searched for "famous woman".
Her male equivalent was Conor McGregor, the Ultimate Fighting Championship lightweight champion.
Deadpool beat other comic book movies including Suicide Squad, Batman v Superman and Captain America: Civil War to become the most searched for movie.
And Strictly Come Dancing edged out Celebrity Big Brother in the TV stakes.
In tech, Apple's iPhone topped the list of the most searched devices, beating Samsung's Galaxy S7 and Google's own Pixel handsets. The Sky Q set-top box was the most popular non-smartphone product.
Some of the queries might require additional context to make sense to many readers:
Google has revealed that "Euro 2016" was its UK search engine's top trending term of the year.