Here's one first name I didn't expect to encounter: Turner.
I wrote last month about how using surnames as first name was more popular a century ago than you might expect, but I neglected to mention the New York Times reporter and editor Turner Catledge. His bylines are featured in the Ken Burns documentary.
Catledge was born in 1901, when the surname-as-first-name trend was still going strong. (It died out by the middle of the 20th century before making a resurgence in modern day.)
Turner was the 555th most popular baby name of 1901. It ranked higher than Jason, Kirk or Jordan.
There's one name that was far more popular, though: Roosevelt itself.
It was 167th that year. Roosevelt peaked in 1905, a testament to the popularity of Teddy Roosevelt. (The name enjoyed a resurgence in the 1930s during the FDR administration, but never reclaimed those highs.)
Currently, Turner is more popular than Roosevelt. It ranks 886th, whereas Roosevelt hasn't appeared in the top 1,000 since 1993.
Maybe the Ken Burns documentary will change that? Time will tell.