The company says trending searches represent queries that "had the highest amount of traffic over a sustained period in 2013 as compared to 2012".
The Fast and The Furious actor Paul Walker -- who died last month in a car crash -- was second, followed by the iPhone 5s, which launched in the fall. The complete top 10:
1. Nelson Mandela
2. Paul Walker
3. iPhone 5s
4. Cory Monteith
5. Harlem Shake
6. Boston Marathon
7. Royal Baby
8. Samsung Galaxy S4
9. PlayStation 4
10. North Korea
In the US, Walker's death was the top trending search on Google, followed by the Boston Marathon bombing and Mandela's passing. The death of Glee star Cory Monteith and the iPhone 5 round out the top five.
Meanwhile, Miley Cyrus, the pop singer who introduced many to twerking, was the most searched person on Google in the US this year. Musicians dominate this category, snagging nine of the top 10 spots.
1. Miley Cyrus
2. Drake
3. Kim Kardashian
4. Justin Bieber
5. Beyonce
6. Rihanna
7. Taylor Swift
8. Selena Gomez
9. Katy Perry
10. Kanye West
Readers can head to Google's Zeitgeist 2013 hub for more details on the year's top searches.